make more resources optional

KOLAB: 3818
ImapResource: Block calls in ResourceTask after cancelTask

If the task get's externally (not by the task itself) cancelled
(i.e. by a dropped connection), the task my be running a job and once it
returns i.e. cancel the task again.

This results in ResourceBase methods getting called while no task is active,
ending in an assert.

This patch simply isolates ResourceTask once cancelTask has been called.
KolabResource: Don't overwrite tag remoteId with old value.

We already stored the tag in TagChangeHelper, so simply call changeProcessed
and don't overwrite the tag again with the original copy.
Move accountwizard from kdepim-runtime -> kdepim