Bump default scala platform version to 2.11
Review Request #4256 - Created Sept. 22, 2016 and submitted
|benjyw, jsirois, mateor, molsen|
- Change default platform version to
2.11.x, which has been the recommended major version for about a year.
- Bump patch versions for built in platforms to latest.
- Downgrade the pantsbuild/pants repo to
2.10in order to upgrade that separately.