Koha profiling

So far ive only profiled opac-search.pl and opac-main.pl, the results are here. From them I can see doing some caching in the C4::Languages module might speed things up. If you look here you can see its doing a lot of work, and it does this work for each page. So if we cache the data structure resulting from the build_langauges_arrayref, and just return that in the subsequent calls, we should win some decent performance.
Ill work on that tomorrow night, and post the new profiles