Editing session while querying causes deadlock

[RoyalMCPE]

Calling InsertComponent or similar that add/remove components from the session while querying causes a deadlock.

This seems to be due to the (query)[https://github.com/AndreasHGK/Peex/blob/14262052507231a0fa059e55837d584da6e12a8d/session.go#L156] calling unlock on defer rather than before the passed function is called.

[andreashgk]

Sorry, I did not see this. I am aware that this happens at the moment, and I will be changing some things around to fix this in the future.

[didntpot]

Any updates @andreashgk?