[Nepomuk] High mutex contention in Nepomuk2::Resource

[Simeon Bird]

>> Would you prefer if I just made start and stop be called
>> from the existing addResource function?
>>
>
> That would change existing behaviour. I'm really not sure right now.

Actually, I think we should just hold the rmmutex during addToWatcher,
and cut out all that moveToThread stuff.
It's a lot cleaner and simpler, and to me the calls feel perceptibly
faster (my test is doing the "link file to activity" thing from the
dolphin context menu, because I don't use kmail). I suspect that
moving around threads has enough overhead that the mutex is just
quicker overall. See code currently sitting in the feature branch
(I'll cleanup the git history before I move it over to KDE/4.10).

Thanks
Simeon