Fix broken link in README
Disable receiving file transfers

 * This was recommended in #575 and #576.

 * Also refactor some common code.
Merge pull request #592 from arlolra/disable

Disable receiving file transfers
Cleanup of previous pull request
Merge pull request #591 from liliakai/patch-1

Fix broken link in README
Fix broken smp

 * Changes in 57028d0569f32bb44a28cef4fe44167f997be8fd fail to register
   this listener.
Merge pull request #593 from arlolra/worker

Fix broken smp