Added module for Freesshd Authentication Bypass (CVE-2012-6066)

This module works against FreeSSHD <= 1.2.6. Tested against
password and public key authentication methods. It will generate
a random key and password.

To use it you need to know a valid username. The module contains
a basic bruteforce methods, so you can specify more than one to try.
Fix regex for hex numbers
Merge branch 'freesshd_authbypass' of https://github.com/danielemartini/metasploit-framework into danielemartini-freesshd_authbypass
final cleanup
Allow negative values for OptInt

[FixRM #7540]
Merge branch 'bug/opt_int_hex' of github.com:jlee-r7/metasploit-framework into jlee-r7-bug/opt_int_hex
psexec_command - Unable to execute specified command: can't convert nil into Integer
Patched as described in Redmine bug #7680
Allow OptInt to pass "" for special reasons

Cheap fix
Merge branch 'bug/rm7680-psexec_command-convert-nil-into-integer' of github.com:lmercer-r7/metasploit-framework into lmercer-r7-bug/rm7680-psexec_command-convert-nil-into-integer
Merge branch 'master' of github.com:rapid7/metasploit-framework into rapid7
Deal with alread-normalized ints

[See #1308][See #1304]
Don't bother nil check, to_s handles it