Make init.sage work

Ideally, this would later be changed to use `attach` again.
Merge pull request #267 from kcrisman/initfix

Make init.sage work
Themes infrastructure
themes rendering and Test theme
themes running except worksheets
Themes on worksheets - Help added
Themes added and Test theme removed
Added themes data files to setup.py
Support for Samuel Ainsworth's new UI themes
Samuel Ainsworth's new UI added as a theme
Templates updates in sync with master for Non-NewUI themes
rebase conflict solved
Prepare themes for issue #210
preparing themes for different error messages when adding users
problem with translations in themes
more problems with translations in themes
more on upload translation in themes
sage newUI converted is a theme
login.html in classical themes synchronized with default nb interface
sample themes updated