Github test: do not try to delete anonymous gist
Github test: use only one auth
Github: RebaseAction - code review fixes
Github: add equivalent of runAndGetValidAuth for convertors
Github: Share project: use CommitMessage for initial commit dialog
Github: Use GithubUserRepository class
Github: parse more repository data
Github: use e.getData(PlatformDataKeys.VIRTUAL_FILE) instead of project.getBaseDir()
Github: create separate util class for URL-processing functions

* create tests for them
* fix some of them
Github: show URL link in error message
Github: fix deprecated exception handler
Github test: move unnecessary assumption
Github: do not show 'Save password' checkbox when it does nothing