Removed upper size limit from encrypt and decrypt_data_symmetric.
Added function to save an encrypted version of the messenger.

Also added some tests.
Merge branch 'master' of https://github.com/irungentoo/ProjectTox-Core
Added some tests.
Added proposal on how to solve all the privacy related problems with the DHT.
Added the shell of onion.{c, h}
All recv packets now handled.
It makes more sense for new_keys() to be in new_net_crypto()
Another packet type added to onion.c
Another packet type is now handled by onion.c
onion.c now handles another packet type.
Added a function to create and send a onion packet.
Fixed small issues in onion.c
Added onion.c to build system and added a test.
Some small cleanups.

TODO: remove old todos that have been done.
Updated TODO.
Some work done on the onion announce part.
A bit of work done on the onion part.
Some work on the onion part done.
Tests added and some fixes for the onion part.