[backend] fix failing obssigner startup on first start
[webui] Apparently chrome also needs autocomplete=off on the form
[api] fix architectures api call descriptions
[webui] port from compass to sprite_factory

compass-rails hasn't seen any commit for 2 months and is not rails 4
ready. and all we need from compass is the sprite functionality, so use
a simpler gem: sprite_factory

The drawback is that the resulting image is in git, so you need to call
bundle exec rake assets:resprite if you add icons
[webui] more preparations for rails 4
[api] implement option to disable access to projects by default. (FATE#315056)
[backend] do not abort the build if some path element does not yet exist
[backend] make the remote_getrev cache work if the project contains multiple links
[api] simplify /published controller, do project listing via source controller now
[webui] the .erb suffix seems redudant for assets
[webui] let's make sprites real images as suggested in sprite_factory

This has the advantage of being able to use :alt
[dist] update gem versions

blacklisting capybara-webkit 1.0 due to
https://github.com/thoughtbot/capybara-webkit/issues/494
[backend] proto projects are not enough data for remote aggregates