Add support for regex with global flag.

[bram-ontoforce]

Regular expressions with a global flag are not working right. The code uses regex.test() and regex.exec(), both increasing an internal lastIndex counter.

For example:

<Highlight search=/brown|jumps/g">The quick brown fox jumps over the lazy dog</Highlight>

will only highlight 'jumps' because the first conditional search.test(remainingCleaned) will move the lastIndex counter right after the 'brown' keyword. search.exec(subject) will then only find 'jumps'.

[bram-ontoforce]

@helior I think this simple change can be relevant for other users, and it extends the functionality because now you can highlight multiple keywords using a regular expression. It does not affect regular expressions without the global flag (because they don't use the lastIndex parameter).

[mihaiserban]

any news on this issue?