Remove msfgui and armitage

This removes the Armitage and MSFGui components from the Metasploit
distribution. You can track the latest stable releases of these
alternate GUIs here:

MSFGui: http://www.scriptjunkie.us/msfgui/
Armitage: http://www.fastandeasyhacking.com/download
Drop msfgui.jar, too.
Landing #1752 - Removes msfgui and armitage

[Closes #1752] - Stable releases can be tracked here:
MSFGui: http://www.scriptjunkie.us/msfgui/
Armitage: http://www.fastandeasyhacking.com/download