build: Make sure historical release notes end up in distributions

Adds the historical release notes to release tarballs and windows
installers.
Merge pull request #3608

de21e8f build: Make sure historical release notes end up in distributions (Wladimir J. van der Laan)
doc: add preliminary release notes for 0.9.0
Cleanup v0.9 release notes
Merge pull request #3642 from petertodd/v0.9-release-notes-formatting-fixes

v0.9 release notes formatting fixes
Merge pull request #3609 from sipa/limitorphanblocks

Limit the number of orphan blocks in memory
Per-peer block download tracking and stalled download detection.

Keep track of which block is being requested (and to be requested) from
each peer, and limit the number of blocks in-flight per peer. In addition,
detect stalled downloads, and disconnect if they persist for too long.

This means blocks are never requested twice, and should eliminate duplicate
downloads during synchronization.