tweaked bug fix - MoveLeafNode() will copy any flag from source node
Fixing tree rebalancing for ref page nodes. Refactoring add node implementation - should be less susceptible for bugs
Skipping long running tests
Making sure that we are always using the _latest_ pager state visible to the transaction, not the global pager state.
minor
write batch optimizations
StorageEnvironment::TransactionCompleted() changes to _trees collection are now atomic
exposing issue with snapshots that are created during transaction commits
fix for race condition between creating a new transaction, reading tree state and commiting tree state
Merge branch 'voron' of https://github.com/ayende/raven.voron into batch_reads

Conflicts:
	Voron/Trees/TreeRebalancer.cs
work in progress --> immutable trees