Making User columns sortable as requested in #147
Changing comments to reflect what functions do
Reformatting to conform to s2Member standards
Fixing sorting on registration time
Adding a few escapes
Encapsulating MySQL table/column names
Switching to  and
SQL security changes
Adding checks to query filter
Additional query filter check
Adding/changing docBlocks, removing generated user and usermeta files
Merge pull request #153 from WebSharks/f-s2Member-147

Making User Columns Sortable