"Rename to .php"

git-svn-id: http://yourls.googlecode.com/svn/trunk@895 12232710-3e20-11de-b438-597f59cd7555
Moved *.php.txt to .txt to prevent spam on misconfigured servers. Fixes issue 1319.

git-svn-id: http://yourls.googlecode.com/svn/trunk@896 12232710-3e20-11de-b438-597f59cd7555