Fixed Optional primitive casts -> String

Now instead uses Objects.toString(...) for them

JavaBytecodeCompiler/src/main/java/org/openzen/zenscript/javabytecode/compiler/JavaExpressionVisitor.java

 import java.util.StringJoiner;
 
 public class JavaExpressionVisitor implements ExpressionVisitor<Void>, JavaNativeTranslator<Void> {
+    private static final JavaMethod OBJECTS_TOSTRING = JavaMethod.getNativeStatic(new JavaClass("java.util", "Objects", JavaClass.Kind.CLASS), "toString", "(Ljava/lang/Object;)Ljava/lang/String;");
+    
 	private static final JavaMethod BOOLEAN_PARSE = JavaMethod.getNativeStatic(JavaClass.BOOLEAN, "parseBoolean", "(Ljava/lang/String;)Z");
 	private static final JavaMethod BOOLEAN_TO_STRING = JavaMethod.getNativeStatic(JavaClass.BOOLEAN, "toString", "(Z)Ljava/lang/String;");
 	private static final JavaMethod BYTE_PARSE = JavaMethod.getNativeStatic(JavaClass.BYTE, "parseByte", "(Ljava/lang/String;)B");
 
 		switch (builtin) {
 			case BOOL_TO_STRING:
-				javaWriter.invokeStatic(BOOLEAN_TO_STRING);
+                if(expression.target.type.isOptional()) {
+                    javaWriter.invokeStatic(OBJECTS_TOSTRING);
+                } else {
+                    javaWriter.invokeStatic(BOOLEAN_TO_STRING);
+                }
 				break;
 			case BYTE_TO_SBYTE:
 				javaWriter.i2b();
 				javaWriter.iAnd();
 				break;
 			case BYTE_TO_STRING:
-				javaWriter.constant(0xFF);
-				javaWriter.iAnd();
-				javaWriter.invokeStatic(INTEGER_TO_STRING);
+                if(expression.target.type.isOptional()) {
+                    javaWriter.invokeStatic(OBJECTS_TOSTRING);
+                } else {
+                    javaWriter.constant(0xFF);
+                    javaWriter.iAnd();
+                    javaWriter.invokeStatic(INTEGER_TO_STRING);
+                }
 				break;
 			case SBYTE_TO_BYTE:
 			case SBYTE_TO_SHORT:
 			case SBYTE_TO_CHAR:
 				break;
 			case SBYTE_TO_STRING:
-				javaWriter.invokeStatic(INTEGER_TO_STRING);
+                if(expression.target.type.isOptional()) {
+                    javaWriter.invokeStatic(OBJECTS_TOSTRING);
+                } else {
+                    javaWriter.invokeStatic(INTEGER_TO_STRING);
+                }
 				break;
 			case SHORT_TO_BYTE:
 				break;
 			case SHORT_TO_CHAR:
 				break;
 			case SHORT_TO_STRING:
-				javaWriter.invokeStatic(SHORT_TO_STRING);
+                if(expression.target.type.isOptional()) {
+                    javaWriter.invokeStatic(OBJECTS_TOSTRING);
+                } else {
+                    javaWriter.invokeStatic(SHORT_TO_STRING);
+                }
 				break;
 			case USHORT_TO_BYTE:
 				break;
 				javaWriter.iAnd();
 				break;
 			case USHORT_TO_STRING:
-				javaWriter.constant(0xFFFFL);
-				javaWriter.iAnd();
-				javaWriter.invokeStatic(INTEGER_TO_STRING);
-				break;
+                if(expression.target.type.isOptional()) {
+                    javaWriter.invokeStatic(OBJECTS_TOSTRING);
+                } else {
+                    javaWriter.constant(0xFFFFL);
+                    javaWriter.iAnd();
+                    javaWriter.invokeStatic(INTEGER_TO_STRING);
+                }
+                break;
 			case INT_TO_BYTE:
 			case USIZE_TO_BYTE:
 				break;
 				break;
 			case INT_TO_STRING:
 			case USIZE_TO_STRING:
-				javaWriter.invokeStatic(INTEGER_TO_STRING);
+			    if(expression.target.type.isOptional()) {
+                    javaWriter.invokeStatic(OBJECTS_TOSTRING);
+                } else {
+                    javaWriter.invokeStatic(INTEGER_TO_STRING);
+                }
 				break;
 			case UINT_TO_BYTE:
 				break;
 				javaWriter.i2s();
 				break;
 			case UINT_TO_STRING:
-				javaWriter.invokeStatic(INTEGER_TO_UNSIGNED_STRING);
+                if(expression.target.type.isOptional()) {
+                    javaWriter.invokeStatic(OBJECTS_TOSTRING);
+                } else {
+                    javaWriter.invokeStatic(INTEGER_TO_UNSIGNED_STRING);
+                }
 				break;
 			case LONG_TO_BYTE:
 				javaWriter.l2i();
 				javaWriter.i2s();
 				break;
 			case LONG_TO_STRING:
-				javaWriter.invokeStatic(LONG_TO_STRING);
+                if(expression.target.type.isOptional()) {
+                    javaWriter.invokeStatic(OBJECTS_TOSTRING);
+                } else {
+                    javaWriter.invokeStatic(LONG_TO_STRING);
+                }
 				break;
 			case ULONG_TO_BYTE:
 				javaWriter.l2i();
 				javaWriter.i2s();
 				break;
 			case ULONG_TO_STRING:
-				javaWriter.invokeStatic(LONG_TO_UNSIGNED_STRING);
+                if(expression.target.type.isOptional()) {
+                    javaWriter.invokeStatic(OBJECTS_TOSTRING);
+                } else {
+                    javaWriter.invokeStatic(LONG_TO_UNSIGNED_STRING);
+                }
 				break;
 			case FLOAT_TO_BYTE:
 				javaWriter.f2i();
 				javaWriter.f2d();
 				break;
 			case FLOAT_TO_STRING:
-				javaWriter.invokeStatic(FLOAT_TO_STRING);
+                if(expression.target.type.isOptional()) {
+                    javaWriter.invokeStatic(OBJECTS_TOSTRING);
+                } else {
+                    javaWriter.invokeStatic(FLOAT_TO_STRING);
+                }
 				break;
 			case DOUBLE_TO_BYTE:
 				javaWriter.d2i();
 				javaWriter.d2f();
 				break;
 			case DOUBLE_TO_STRING:
-				javaWriter.invokeStatic(DOUBLE_TO_STRING);
+                if(expression.target.type.isOptional()) {
+                    javaWriter.invokeStatic(OBJECTS_TOSTRING);
+                } else {
+                    javaWriter.invokeStatic(DOUBLE_TO_STRING);
+                }
 				break;
 			case CHAR_TO_BYTE:
 				break;
 				javaWriter.i2l();
 				break;
 			case CHAR_TO_STRING:
-				javaWriter.invokeStatic(CHARACTER_TO_STRING);
+                if(expression.target.type.isOptional()) {
+                    javaWriter.invokeStatic(OBJECTS_TOSTRING);
+                } else {
+                    javaWriter.invokeStatic(CHARACTER_TO_STRING);
+                }
 				break;
 			case ENUM_TO_STRING:
 				javaWriter.invokeVirtual(ENUM_NAME);