Adding failing test for RavenDB-1090
Merge branch 'RavenDB-1090' of git://github.com/ayende/ravendb into RavenDB-1090

Conflicts:
	Raven.Tryouts/Program.cs
RavenDB-1090 Properly implementing tests
RavenDB-1090 Update synchronization etag when bulk inserting is being done
RavenDB-1090 Since concurrent writes to database are supported it might happen that the highest etag in the indexing batch is lower than etag indexed in last cycle (because now we sometimes have to go back because of etag synchronization)
RavenDB-1090 Temporary disabled getting documents from memory in PrefetchingBehavior
RavenDB-1090 Temporarily disable docs merging to make sure that we don't read from memory
Better check if index is stale - except from ETag comparison also check if the map indexing task is in progress
RavenDB-1090 Prevent reading from memory if the etag that we want to start indexing does not match
RavenDB-1090 Minor - don't insert so huge number of docs in test
Merge branch '2.5' of git://github.com/ayende/ravendb into RavenDB-1090
Merge branch '2.5' into RavenDB-1090

Conflicts:
	Raven.Database/DocumentDatabase.cs
RavenDB-1090 Use smaller number of docs in bulk insert indexing test
RavenDB-1103 Rewriting PrefetchingBehavior for better support of concurrent transactions
RavenDB-1103 Handle the delete operations in PrefetchingBehavior
Fix locking in ConcurrentJsonDocumentSortedList
Removed unused nested class
Replication task uses the prefetching too
Fixing tests because of changing PrefetchingBehavior implementation
RavenDB-1103 Fixing Etag incrementation when detection of deleted docs is being done