[api] trying to make the event class autoloading less fragile
[webui] replace project_or_package_link partial with a helper function

This allows much saner programming than in erb
[webui] rename patchinfo model to WebuiPatchinfo to avoid name clashes

Namespaces are fine, but somehow rails' autoload breaks them more often
than not ;(
[webui] remove distribution model
[webui] do not query the package issues again - they are in the database
[webui] do not query the API for home#index

Use model queries instead.
[api] cache the result of project_or_package_link

To make this work, I added a new model CacheLine that remembers in the
database if something for a package or project was cached. If that
package is changed, the event creation will then delete the cache line
[api] try to fix coverage results
[webui] move the assets into the main app - they end up in /public anyway
[api] pimp the coverage by fixing a typo :)
[api] support source update hook via token

can be used for example for a github service integration
[api] ensure that users in state deleted are not visible