Add support for index.html in gh-pages

[XsubinX]

There could be multiple maven sites per repository. It will be nice to have an index.html created/modified as part of site goal.

For example if the path configuration is like this

<path>${project.version}</path>

There will be multiple folders created within gh-pages branch for each version of the project. And developers/users will be forced to guess the exact version open the maven site.

It will be great if there is a gh-pages/index.html which can list links to all the available maven site for a particular repository.

Since GitHub will not allow external scripts to run within gh-pages, the only option left is the github-maven plugin.

Thanks
Subin