Module Image Assets

Allows for calling images stored in a module's assets folder with the assets library. To use pass the module name to the image url.

for example: site_url('images/default.png?module=blog');
will provide an image stored in [...]/bonefire/modules/blog/assets/images/default.png
Module Image Assets Fix

fix $img_file override I missed.
Fix code statement.
Documentation for Module Image Assets
Merge pull request #931 from thedudeguy/master

Can now use module-based images with the images controller.
Update MY_Model.php

validation return result is not checked in update function
Merge pull request #975 from spheregendev/patch-1

Validations at the time of update
Fixing potential security breach.
Load activity model

Because it's being used at line 231
Using helper instead of model to log activity
Merge pull request #1043 from benrogmans/patch-1

Correct an missed log_activity switch over.
Merging changes that had been inadvertently put into master instead of develop branch.