AURORA-1485: TaskConfig default container value breaks client library generation for GO
AURORA-1485: TaskConfig default container value breaks client library generation for GO

When generating the client api library for go the default containerizer used as a hack for AURORA-1185 breaks and causes the client lib to not be generated correctly. The default value for the optional field `container = { "mesos": {} }` is not necessary as it is defaulted in java code on the api side.

Tracking this down it looks like the default value was a last minute addition based on some review comments and is not necessary or used anywhere.

Testing Done:
Passes all java/py tests in ./build-support/jenkins/build.sh
Passes all e2e tests in ./src/test/sh/org/apache/aurora/e2e/test_end_to_end.sh

Bugs closed: AURORA-1485

Reviewed at https://reviews.apache.org/r/38389/

rdelval/aurora,protochron/aurora,crashlytics/aurora,apache/aurora,rdelval/aurora,rdelval/aurora,medallia/aurora,thinker0/aurora,rdelval/aurora,mschenck/aurora,protochron/aurora,mschenck/aurora,medallia/aurora,crashlytics/aurora,apache/aurora,protochron/aurora,medallia/aurora,crashlytics/aurora,mschenck/aurora,thinker0/aurora,rdelval/aurora,apache/aurora,thinker0/aurora,protochron/aurora,thinker0/aurora,apache/aurora,apache/aurora,protochron/aurora,thinker0/aurora,protochron/aurora,crashlytics/aurora,rdelval/aurora,medallia/aurora,medallia/aurora,crashlytics/aurora,medallia/aurora,mschenck/aurora,mschenck/aurora,mschenck/aurora,thinker0/aurora,crashlytics/aurora,apache/aurora