Adding Buffalo Linkstation NAS Login Scanner

I have added a login scanner for the Buffalo Linkstation
NAS.  I have been testing against version 1.68 of the
firmware.  Also included are some specs for this module.
Rescuing from JSON Parse

Previous code was not using any sort of exception handling
for parsing the response body.  I have added a rescue block
for JSON errors to remedy this problem.
Refactoring Success Case

I have refactored the code so that it will work with
non-root accounts.
Allow FTP server exploits pick a PASV port

This makes it somewhat easier to use FTP server exploit modules in
somewhat more restrictive networks, where you might only have a few
inbound ports to choose from.
Allow PASV port specification, lands #4086
With 66 days left in 2014, may as well update
Land #4087, COPYING copyright year update
Land #3987 - Buffalo Linkstation NAS Login Scanner