added driver_loaded post meterpreter module
Changes to Service mixin
Applying changes
Class constants and Regex added
Beautify use of Regexp
Update against upstream
Include Msf::Post::Windows::Error
Merge pull request #4 from jvazquez-r7/review_2763

Update against upstream
Beautify description
Land #2763, @bmerinofe's driver_loaded post meterpreter module