Fix the client NetworkWorker being in the "common" namespace.
Merge pull request #12 from Neki/topic/bf_fix_namespace

Fix the client NetworkWorker being in the "common" namespace.
Add virtual destructor to the base Event class.
Add the -Wnon-virtual-dtor flag when compiling.
Merge pull request #13 from Neki/topic/bf_add_virtual_destructor

Add virtual destructor to the base Event class.
Add a GameTimer class to provide reference timestamps during a game.
Add sending and receiving ping_packets.
Check protocol and version of received datagrams.
Add some logging.
Fix confusion between packet ID and packet type.
Log received packet ID.
Fix GameTimer namespace.