Last commit switched from raw arrays to associative
arrays. That leads to json_encode() to generate an
object instead of an array, ultimately leading to
problems with the rest of code expecting an array.
By using array_values() we are moving back to the
non-associative array.
Also, fix some file permissions.
The improvements include:
* HTMLPurifier cache is stored in localcachedir
* allowobjectembed changes are not ignored any more
* the cache keys include revision and all options which makes
this suitable for local caches on cluster nodes
* unchanged test is replaced by "true" value which should
significantly improve performance
* removal of purge_all_caches() hack for directory recreation
* comments and coding style cleanup
Rajesh Taneja