add some features.

    1) refactor Compiler class.
    2) refactor some testing codes by Test::Compiler::Parser.
    3) fix parsing bugs.
       - return && postposition statement
       - function takes block argument like 'try { ... } catch { ... }'
       - map/grep
       - missing semicolon at end of statement
    4) add testing codes generator.
    5) improve detecting anonymous hash reference algorithm. (support return {} or +{})
    6) support reference chain without pointer token.
fix MyBuilder.pm and debug log