IDEA-131531 Push dialog: it is not clear that push target (remote branch in Git, repository URL in Mercurial) can be modified

* vcsLinkedText used  instead of additional type of components, others removed;
* editable text component interface added as a special type which start tree edit mode;
* linkedText components rendered themselves;
* linkedText components underlined when under cursor or under selection
Merge remote-tracking branch 'origin/master'
unnecessary hierarchy removed
maven: use "idea." prefix for IDEA specific property (maven3.use.compat.resolver)
maven: check for existing project in maven actions. It possible to process actions without an open project
related issue - https://youtrack.jetbrains.com/issue/IDEA-132152