MetadataConnection cannot be initialized with javaTime flag set to true

Currently `javaTime` parameter of the `TypeMapper` object is always set to false what prevents from using modern Java data/time objects.

https://github.com/forcedotcom/wsc/blob/1c6d1a4f40cb2de34485b99dd5f00d5ab3394c54/src/main/java/com/sforce/ws/codegen/templates/connection.st#L19

Can we get this parametrized to be more flexible? Unless I am missing something on how to get that right without code changes.

Any help would be appreciated!