[webui] remove the workaround for old webkit issue

https://github.com/thoughtbot/capybara-webkit/issues/444
[backend] don't do setchanged for package source changes on another partition
[webui] random fixes from crash reports
[webui] test replying to comments
[backend] add random component to 'rescan' timeout
[backend] do not upgrade remote project events
[backend] add a way to signal that a project on a different partition is gone
[backend] add "withchangesmd5" parameter to package info query

Done so that the API needs less requests to gather the information
it needs.
[backend] enforce sha256 for newer rpm-md repositories
[api] refactor status controller
[api] refactor one more function
[api] srcmd5 should probably not be a class variable but an instance variable
[api] replace linked_packages with backend_packages

Also saves md5sum for all packages not just links
[activexml] do not retry failed connections

This was needed back in lighttd days
[backend] do not use xrpc_setchanged for linked packages

setchanged uses an unfair unshift to bring the prps to the front.
[api] fix more of my stupid copy&paste programming

Unfortunately build status is hard to test during test suite as we don't build ;(
[api] make sure Event::Base.not_in_queue is quick
[api] fix fixtures, define issues from real source and rescan all sources after fixtures setup.
[backend] improve/cleanup linked package handling a bit
[backend] refactor putprojectconfig a bit