Minor refactoring
Refactoring to a nicer pure memory impl
Don't allow direct writing to memory
We don't do anything with dirty pages right now, anyway
Midway through a commit to introduce free space recovery - stopped to implement iterators
Adding support & tests for iterations
More work on getting free space to work
Merge branch 'mmdb' of github.com:ayende/temp.raven.storage

Conflicts:
	Nevar/Impl/Pager.cs
	Nevar/Impl/Transaction.cs
Work to fix rebalancing bug