Less specific syntax groups regexps

Instead of targetting the regular expressions to very specific syntax groups (ie: javaScriptDocComment), which make the indent script not compatible with other syntaxes (ie: jsComment), more generic versions are used which should still match the same groups by using case insensitive search and shorter patterns (string, regex and comment).

This modification works for the bundled syntax with Vim 7, the syntax version provided with the indent script as well as with this new javascript syntax: https://github.com/drslump/vim-syntax-js