Lita 3.0 compatibility

Updated dependencies to 3.0. The major change was the introduction of
frozen configuration during plugin init. Moved variable settings into
an options property.
Merge commit 'abcedbd41b25129f39b34ead1daa510998a4a7fd' into develop

* commit 'abcedbd41b25129f39b34ead1daa510998a4a7fd':
  Lita 3.0 compatibility