[webui] Testcases for the patchinfo-editor and some fixes

- Finally, the patchinfo-editor has some testcases
- Added some id-tags where necessary in the views
- catch error if a connection to the bugzilla can't be established (like in the testsuite)
- catch 401-error if an unauthorized user tries to edit the patchinfo via direct-url
- Removed unused get_tracker-function. This is deprecated since I use another format for adding issues to patchinfos (now foo#bar instead of selecting a tracker and add the id seperate)