last minute link fixes; remove support links
fix broken links in case_study
more last-minute fixes
Merge branch 'release/2.5.0' of github.com:caskdata/cdap into release/2.5.0
broken link in api page
Merge branch 'release/2.5.0' of github.com:caskdata/cdap into release/2.5.0
fixed broken links in api page
Restore build script broken in Wednesday's bad commit.
Merge remote-tracking branch 'origin/release/2.5.0' into develop

Conflicts:
	cdap-docs/developer-guide/source/_examples/first-app.rst
	cdap-docs/developer-guide/source/tools.rst
Fix the race condition between program stop and program status check and start.
- They should be using the same way to check if a program is running

Also some code refactoring to make the code cleaner
Plus a concurrency bug fix in getting program status for MR in workflow
Use future to carry the workflow client result instead.
fix checkstyle issue.
(CDAP-329) Upgrade to netty-http 0.5.0
Upgrade netty-http version in examples.