removed crazy logic
changing buffer cache soft throttling to scale based on cache size
moving transaction throttling limit changing logic into the throttler
changing disk-backed queues to have a base cache size of 2 MB
code review cleanup
Merge branch 'v1.12.x' of github.com:rethinkdb/rethinkdb into v1.12.x
draft release notes for 1.12.1
Improve build-rpm.sh script
Unset DESTDIR in pkg.sh and edit v8 CXXFLAGS
Remove a reference to the old support.mk
Always use --host flag when compiling libunwind
Use the correct architecture flag when building RPM
Fix v8 build error on centos
Merge branch atnnn/2183 into next

Closes #2183
Closes #2176
Closes #1491

Review 1380 by @mlucy
second draft
Merge pull request #2186 from rethinkdb/atnnn/notes

Release notes for 1.12.1