Core: default plugin icon changed
PY: show categories.
PY: store categories.
PY: properly join tags in EntriesModel.
PY: support qobject_cast for TagsLineEdit.
PY: support editing the Categories column.
PY: keep track of known categories in OperationsManager.
PY: support editing the categories in ops view delegate.
PY: properly update categories for ExpenseEntries.
Merge branch 'master' of github.com:0xd34df00d/leechcraft
Util: check if tagsUpdated() signal exists in the model.
PY: use TagsLineEdit in OpPropsDialog.
LMP: always return empty MediaSource if queue is empty.

Fixes #1070.
LMP: clear last song on player clearing as well.
LMP: clear current source on stops and playlist clears.

Fixes #1071.
LMP: support drags from FS model/tree, closes #1067.
LMP: replace queue on playlist activation.

Somewhat relates to #1068.
PY: generated translations.
VB: don't own the conversation in the buddy.

Fixes #1029.
VB: better account disconnection on going offline.