Added a filter function
Some xss fixes

filtering $id reflection
Removed duplicate install.php from inc folder
fix for #497

xss fixes
dir traversal protection for ajax.php

This file will go away soon, but some protection for now.
removed dup
attempt to fix 3.0 upgrade issues.
untested
Merge branch 'hotfixes' of github.com:GetSimpleCMS/GetSimpleCMS into hotfixes
Merge branch 'hotfixes'

Conflicts:
	admin/edit.php
	admin/inc/common.php
	admin/inc/security_functions.php