[CHAST] Refactoring ANTLR

Refactoring based on ANTLR and its grammars.

Structure

• base: Base operations for running refactorings on the basis of ANTLR
  • java: Base Classes required by some of the lexers and parsers.
  • kotlin: Actual code
    • strategies: Refactoring strategies for doing certain operations like rearranging or replacing nodes
    • This is also the entry point for loading the different lexers/parsers.
• refactorings: Home of all the refactorings currently implemented
  • rearrange_class_members: Refactoring for rearranging class members according to a user specified configuration.
    • Currently supported languages: Java, Kotlin, C#
    • A chast recipe is available with some tests available. Check the main repository for a demo.
  • remove_double_negation: Refactoring for eliminating double negations like if(!!isEmpty) -> if(isEmpty)
    • Currently supported languages: Java, Python
    • A chast recipe is available with some tests available. Check the main repository for a demo.