Ressurect demos using gh-pages branch

[nyov]

I created a gh-pages branch, so the demos could be visited again.

While doing that, I had to remove the Packager submodule to avoid page build failure.
So since the branch contents diverged from the develop branch anyway, I also removed several other files that are unnecessary in that branch. (More could be removed, anything except Demos and Docs I believe.)

The downside there is that to keep contents of develop and gh-pages in sync, merges will need to happen when docs or demos change in the future.
(Or to avoid that, they could be removed entirely from the code branches and only kept updated in gh-pages.)

Preview: https://nyov.github.io/mochaui/

Hope this helps to fix #152

[nyov]

Ack! The PR wants to be merged into mui:develop, but that's wrong of course.
(Dont merge!)
If interested, please manually pull and push to a new gh-pages branch here, instead.