1. Fix yamllint errors in .yamllint file(!)

YAML lint is currently failling on its own configuration file,
.yamllint. This change fixes the issues.

2. Run bindep role in Zuul jobs

This fixes an issue where libffi is not available.

Change-Id: Ic08a8e53a6905a68f0fe26d4b28184e62a64324f

This patchset implements yamllint test to all *.yml
files.

Also fixes syntax errors to make jobs to pass.

Change-Id: I3186adf9835b4d0cada272d156b17d1bc9c2b799