parser for Perl quoted strings
tests using alternate delimiters for regexes
quotedPair parser to match quote pairs as in s///
substitution with single-char ('/' only for now) and using paired delimiters (brackets)
more tests using different delimiters
Perl6-ish interpolation of double-quoted strings
handle more escaped characters in strings
unicode literal support and subroutine call fix
work around the fact that stringifying MoeStrObjects adds delimiting
double quote chars.
change serialized ast representation for double-quoted strings
few tests for interpolation
Merge pull request #121 from MoeOrganization/prakashk/quotesque

regexes with brackets as delimiters and double-quoted string interpolation