Force perl encoding

Hi @midnitesnake,

https://github.com/rapid7/metasploit-framework/pull/3561 has been finally landed, and now modules have  a mechanism to prefer perl encoding over echo encoding, when echo -e isn't available as expected. This pull request updates your branch with changes in rapid7 master, and updates your module to force perl encoding. There are a lot of commits because your branch was super out of date versus rapid7/master, don't be scared :) The only change to your module is: https://github.com/jvazquez-r7/metasploit-framework/commit/373ce8d340786bba8148fdd5cd561b32c157cb7c

I have not a solaris machine to test which the perl encoded paylaod is working. Do you mind to give a chance and land this pull request if everything is working? thanks!