NHibernate performance improvements

I picked up a couple of ideas off the ALT.NET mailing list.

• To speed up start-up times, put all your mappings into a single XML file. I would recommend keeping the files separate during development and having a step in your build process to concatenate them (http://ayende.com/Blog/archive/2007/10/26/Real-World-NHibernate-Reducing-startup-times-for-large-amount-of.aspx).
• Use NHibernate Proxy Generator to generate static proxies (http://code.google.com/p/nhibernateproxygenerator/).

These optimisations are only relevant when you have hundreds of entities.