msfconsole 'edit' command

Useful for quick editing a module during development / bug fixing. I
don't really see a security issue with running a command defined in the
user's VISUAL or EDITOR environment variables;  if the user can run
msfconsole to begin with, there are better ways to get into trouble.
Use Rex::Compat.getenv instead

Also, this would deprecate out the editor plugin.
Remove the editor plugin.

Sorry, @jcran, didn't see that this was available. Turns out, this
feature is almost identical to the editor plugin, so this effectively
promotes 'edit' to a first class command.
Methodize the editor variable as local_editor
chmod -x cmdstager_printf.rb
Add Beetel Connection Manager NetConfig.ini BOF
Fix mimikatz error when password is nil

In some cases the password value that comes out of mimikatz results
is `nil`, instead of an empty string. This fixes this so that if
the string is `nil` is falls back to an empty string, resulting in
the call to `gsub` working instead of failing.
Land #2590, gsub nil fix for mimikatz
Add ProcessMaker Open Source Authenticated PHP Code Execution
Land #2588, @wvu-r7's permissions change for cmdstager_printf.rb
Clean processmaker_exec
Land #2591, @bcoles's exploit for ProcessMaker
Add Win7 SP1 to WinXP SP3 target
Add short comment on why the padding is necessary
Fix style
Land #2589, @wvu-r7's exploit for OSVDB 98714
Add @brandonprry's seven new modules

Already reviewed privately, no associated PR.
Update references for FOSS modules
Typo fix
Un-dupe References for ispconfig