tweaks to prefetcher --> load from disk average timing as additional treshold for fetching docs from batch
Merge branch 'master' of github.com:ayende/ravendb into RavenDB-2332-3.0
WIP
Merge branch 'master' of github.com:ayende/ravendb into RavenDB-2332-3.0

Conflicts:
	Raven.Database/Prefetching/PrefetchingBehavior.cs
	Raven.Database/Storage/Voron/StorageActions/DocumentsStorageActions.cs
fix after bad merge
Merge branch 'master' of github.com:ayende/ravendb into RavenDB-2332-3.0
WIP -> refactoring of DebugJournal + debug endpoint for etags in voron storage
WIP on fix of 2332 issue (not finished)
Merge branch 'master' of github.com:ayende/ravendb into RavenDB-2332-3.0
fix to RavenDB-2419
removed unneeded endpoint
removed debugging code
removed not relevant code
Merge branch 'RavenDB-2419' of https://github.com/myarichuk/ravendb
Avoiding errors in tests