[plexus-compiler] (8 commits) ...Merge branch 'update-to-version-2.x'

[Michal Srb]

Summary of changes:

  964139d... Update to upstream version 2.1 (*)
  201f453... Update to version 2.1 (*)
  7d924ae... Build with original POM files (*)
  4c98fed... Bump release version (*)
  6facf15... Remove auxiliary aliases (*)
  4f7059a... Update to upstream version 2.2 (*)
  158693c... Add license file (Resolves: #903268) (*)
  0225a9e... Merge branch 'update-to-version-2.x'

(*) This commit already existed in another branch; no separate mail sent