Add a connected_event parameter to the ConnectbackServer.

This allows callers to be notified when a connection is
received through a threading.Event that they can wait() on.
Make TrojanDropper download to /var instead of /tmp
Add connected_event to the TrojanDropper as well
Add connected_event parameter to the ConnectbackServer
Merge branch 'master' of github.com:tcoppi/bowcaster

Conflicts:
	src/bowcaster/servers/connectback_server.py
Merge branch 'master' of https://github.com/zcutlip/bowcaster

Conflicts:
	src/bowcaster/payloads/mips/trojan_dropper_payload.py
	src/bowcaster/servers/connectback_server.py
Merge pull request #1 from tcoppi/master

Add connected_event parameter to the ConnectbackServer and TrojanDropperServer and use /var for Trojan Dropper