[fix] - and _ are also valid characters for youtube video ids

git-svn-id: file:///var/local/code.tiki.org/tikisvn/trunk@47242 b456876b-0849-0410-b77d-98878d47e9d5
[FIX] filegals & elfinder: Respect perms on special galleries (like user ones)

git-svn-id: file:///var/local/code.tiki.org/tikisvn/trunk@47243 b456876b-0849-0410-b77d-98878d47e9d5