[BACKLOG-186] - Need to provide user with a decent message when the repository is not availabe

changed error message according to UX feedback
slightly changed logic for process launch of Repository Explorer failure
added failure processing for JobDialog: extraTabs

[BACKLOG-186] - Need to provide user with a decent message when the repository is not availabe

change ctor of KettleRepositoryLostException to rely on super getMessage() and getLocalizedMessage()
checkstyle

[BACKLOG-186] - Need to provide user with a decent message when the repository is not availabe

fix typo in the message

[BACKLOG-186] - Need to provide user with a decent message when the repository is not availabe

move the second message to the same package with repositoryLostException
in order to avoid strings as package names while loading string resources