~ Fix documentation markup.
~ Add documentation to client info.
~ Fix documentation and typos.
+ Add bitfield module.
~ Reorganize modules.

All peer location & identification & information stuff should be placed
in Network.BitTorrent.Peer now.
+ Add some bitfield operations.
+ Add initial tests for bitfields.
+ Add other bitfield operations.
+ Add tests for bitfield min & max.
+ Add more properties for bitfield operations.
+ Add benchmarks for bitfields.
+ Performance improvement in findMax & findMin.
+ Add some test cases for findMin & finMax.
+ Add bench for intersection & union
~ Performance improvements: binary bitfield operations.
+ Add Selection module skeleton.
+ Add some benchs.
+ Add shorthand commands.
~ Minor changes.
+ Add bitfield completeness function.