Upgrade to rx 1.0.0-rc.7; Add back pressure buffer to match prior behavior.
Merge pull request #89 from Netflix/fix-rx

Upgrade to rx 1.0.0-rc.7; Add back pressure buffer to match prior behavior
[Gradle Release Plugin] - pre tag commit:  '0.2.11'.
[Gradle Release Plugin] - new version commit:  '0.2.12-SNAPSHOT'.
Update readme
Merge branch 'master' of github.com:Netflix/PigPen

# By Bob T Builder
# Via Bob T Builder
* 'master' of github.com:Netflix/PigPen:
  [Gradle Release Plugin] - new version commit:  '0.2.12-SNAPSHOT'.
  [Gradle Release Plugin] - pre tag commit:  '0.2.11'.
Merge branch 'master' of github.com:Netflix/PigPen into cascading