replaced double-quoted code strings passed to eval
with single-quoted ones to prevent interpolation
evaluate closures in double-quoted strings in a new environment
bunch more tests for interpolation stolen from Perl6 roast
quote operators: q, qq, qw, qr and qx
fix rule for quoteRegexOp
Merge pull request #122 from MoeOrganization/prakashk/quote-ops

quote operators and more tests