Add firefox 15 chrome privilege exploit.

* Moves the logic for generating a firefox addon into its own mixin
* Updates the firefox_xpi_bootstrapped_addon module to use the mixin
* Module only works if you move your mouse 1px in any direction.
It helps to actually commit the exploit.
Move addon datastore options into mixin.
Move datastore options to mixin.
Clean up code. Test version support.

* Using #get in Object#defineProperty call makes the payload execute immediately
on all supported browsers I tested.
* Moved Ranking to Excellent since it is now 100% reliable.
Tidy whitespace.
Fix include reference.
Move comment.
Update versions, 4.0.1 does not work on windows.
Use a smaller key size, harder to spot.
Add a patch for 15.x support.

* Also add authors i forgot, oops
Update description with new version support.
Add support for Procs in browserexploit requirements.
Update module to use sinn3r's beautiful browserexploitserver.
msftidy it up.
Use the right disclosure date.
Land #2781 - Firefox 5.0 - 15.0.1 __exposedProps__ XCS Code Execution