a simple PHP record sorter class

Not for the first time I needed to sort arrays of arrays in PHP (structures like tiny DB tables).  I have previously written little wrapper functions round usort, but decided this time to make a small class. It is a simple, but generic utility, so popping it up in case useful to anyone.

The rest of this post has moved to a permanent page at:

http://www.alandix.com/blog/code/sorter/