Upgrade to ASM 6.2

    experimental support for the upcoming JDK 11 features (nest mates and ConstantDynamic)
    code quality and readability of commons package improved a lot
    bug fixes
        317817: Allow Kotlin back-tick identifiers by CheckMethodAdapter
        317821: Regression in 6.1: "new Frame" instead of "newFrame" in Analyzer
        317822: ACC_DEPRECATED flag (or corresponding attribute) is lost if the constant pool is copied
        317823: Computing maximum stack size does not work correctly with JSR/RET instructions present
        317824: ACC_SYNTHETIC attribute is lost for < Java 1.5 if the constant pool is copied
        317825: idem
        317827: Computing maximum stack size does not work correctly with dead code present