added support for extended colors (xterm 256 and 24 bit rgb)

[JoeMerten]

This PR adds support for extended color like esc[38;5;<index>m or esc[38;2;<r>;<g>;<b>m when parsing.
Need this to implement extended color support in jenkins-ansicolor-plugin. See also #89 and #96.

[ssbarnea]

@gnodet Can we have this reviewed and merged? Seem to be needed for the new release of jenkins-ansicolor.

[ssbarnea]

@gnodet Thank you! I performed a new build of jenkins-ansicolor-plugin and tested it and I can confirm that this patch fixed it. Now we only need 1.15 to be released so we can officially consume it.

[ssbarnea]

@gnodet or @hboutemy Can we have a 1.15 released? I cannot make an official build that uses a git branch of jansi. I did this for testing, worked really well, time to get 1.15 jar uploaded to maven.

[hboutemy]

before releasing JAnsi 1.15, I'd like to enhance HawtJNI first: https://issues.apache.org/jira/browse/MNG-6186
I'll provide a PR soon

[gnodet]

Sorry, I missed your latest comment. Jansi 1.15 has been released, but let me know in case you need a new release.

[hboutemy]

releases are cheap: no big issue, better to have a release now than a promise to do it later
I'll keep you informed
notice: you don't seem to track milestones with GitHub issue tracker, is it intended? It would be easy and useful to track what goes into each release

[hboutemy]

fusesource/hawtjni#35 created