cleanup ConfigImportHelper
(cherry picked from commit 6370a1a)
we don't need to remove plugin_ui.xml anymore — installed plugin list is not stored
(cherry picked from commit 6c49f93)
IDEA-131750 Fail to start after update from WebStorm 8 to WebStorm 9 (problem with TFS plugin)
(cherry picked from commit fdb0244)
IDEA-CR-802 fix "same conditions?"
(cherry picked from commit 0854b89)
IDEA-76479 (helper method)