Sync up PurdueNext changes with core
A couple more sync items with PurdueNext
[COM_CRON] Some minor clean up of models
[PLG_COURSES] Plugin language files moved in J25
Fixed docblock and modified set method to allow for method chaining
[PLG_COURSES_GUIDE] Fixed issue with ensure overlay scrolls with background
[PLG_COURSES_PAGES] Fixed issue with file uploader and minor style issue with edit links over content
[PLG_COURSES_DISCUSSIONS] Fix for category delete action not being honored
[COM_COURSES] Check for index before attempted use.
[PLG_COURSES_NOTES] Fixed URL nto including current section and lecture view not filtering by section.
[PLG_MEMBERS_BLOG] Minor clean up and made sure all language strings in language file.
[PLG_GROUPS_BLOG] Minor clean up and made sure all language strings in language file.
[PLG_GROUPS_FORUM] Made sure all language strings in language file.
[PLG_MEMBERS_COURSES] Made sure all language strings in language file.
[PLG_MEMBERS_GROUPS] Made sure all language strings in language file.
[PLG_MEMBERS_POINTS] Made sure all language strings in language file.
[PLG_MEMBERS_BLOG][PLG_MEMBERS_COURSES] Fix for quotes in string in language file.
[COM_USERS] disable password fields in Joomla com_users component
[PURDUENEXT][#432][COM_COURSES] change data type of asset group description field to text
[COM_RESOURCES] Disabled unzippng code from attachments and added ability to add links, drag and drop