Fixes for Travis CI builds
Add an optional 'ZKMapListener' to ZooKeeperMap which fires as nodes are added, changed, and removed.
Add tests and changes based on feedback

from 9639406e2cb5d58245c8e839c2ee9295dde3915f
Merge pull request #166 from eric/travis-ci-fixes

Fixes for Travis CI builds
Add null check for listener and other small cleanup
Fix noop listener based on feedback
Fix constructor that was passing null
Merge pull request #165 from eric/zookeeper-map-listener

Update to #11: "Add an optional 'Listener' to ZooKeeperMap which fires as nodes are added, changed, or removed"
Fixup the checkstyle task to skip synthetic targets.

This fixes a regression introduced by changes in a489c3ad to
distinguish codegen targets like java_thrift_library from the
synthetic targets they inject to own generated code.
Merge pull request #169 from jsirois/jsirois/pants/fix_checkstyle_synthetic

Fixup the checkstyle task to skip synthetic targets.
Fixup the PrepareResources task to properly augment the classpath in
the exclusives regime.

Undo pingpong example workaround.

Perform minor cleanups on exclusives related code read to grok this
fix.
Keep the && chain alive in the travis build, a failed pants build should fail fast.
Cleanups from internal review of ZooKeeperMap(Test)
Remove a superfluous encode() call.

dist.get_metadata() returns a string (NOT a unicode). It is not
logically sound to call encode('utf-8') on a string, only on a
unicode. In fact, string probably shouldn't have an encode() method
at all.
Merge pull request #174 from foursquare/master

Remove a superfluous encode() call.
Merge pull request #171 from jsirois/jsirois/pants/issue_160

Fixup the PrepareResources task to properly augment the classpath in the exclusives regime.
Revert "Keep the && chain alive in the travis build, a failed pants build should fail fast."

Eric knew what he was doing here of course :/

This reverts commit cf28c12cf8c9f63174ee07d56ed76873baf57d9a.
Merge branch 'master' into betterscala