capacity: remove unused threadpool

[yadvr]

This removes unused injectables and threadpool.

Types of changes

• Breaking change (fix or feature that would cause existing functionality to change)
• New feature (non-breaking change which adds functionality)
• Bug fix (non-breaking change which fixes an issue)
• Enhancement (improves an existing feature and functionality)
• Cleanup (Code refactoring and cleanup, that may add test cases)

GitHub Issue/PRs

Screenshots (if appropriate):

How Has This Been Tested?

Checklist:

• I have read the CONTRIBUTING document.
• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
  Testing
• I have added tests to cover my changes.
• All relevant new and existing integration tests have passed.
• A full integration testsuite with all test that can run on my environment has passed.

@blueorangutan package

[blueorangutan]

@rhtyd a Jenkins job has been kicked to build packages. I'll keep you posted as I make progress.

[blueorangutan]

Packaging result: ✔centos6 ✔centos7 ✔debian. JID-1956

[nvazquez]

LGTM

[blueorangutan]

@rhtyd a Jenkins job has been kicked to build packages. I'll keep you posted as I make progress.

[yadvr]

Thanks all, I'll merge this based on travis test results and code reviews. Since this is a cleanup in java, build and packaging jobs + travis smoke tests are good enough for evaluation.

[blueorangutan]

Packaging result: ✔centos6 ✔centos7 ✖debian. JID-1964