fixed DebugJournal
added the option to dump only stream length for faster processing
fixed issue with releasing entries from scratch - there is a possibility that transaction contains more than one page from scratch that points to the same page number (ModifyPage), which in the end causes duplicates in the _unusedPages
added a test for RavenDB-1707
RavenDB-1700 Fixing the order of freeing scratch pages: we have to free pages of unused journals first before the other journals because otherwise a read transaction could read an outdated page from the older and not relevant journal
Merge branch 'RavenDB-1700' of https://github.com/arekais/ravendb into New3