Use platform_family instead of platform

This will allow the ibm_powerkvm platform to be recognized and will
simplify uses of multiple platforms from the same family.

Change-Id: Iebf2aad9f3b4649fb5c27d2fc93ee60c67e42737
Partially-Implements: blueprint add-ibm-powerkvm-enablement
Implements: blueprint platform-family
Add .cookbooks to .gitignore

Change-Id: I8bee67cdc3b95ae06efff371e56bdd7fc58e7f5b
fix metadata database depends

database pulls in mysql, new mysql v5 is not backward compatible.
Need to pull in mysql depends first at v4, then pull in database.

Change-Id: Ib27c9c77e7eaf25b11a3f4fb7871a6b3a8acba62
Related-Bug: #1300524
Merge "Add .cookbooks to .gitignore"
Merge "Use platform_family instead of platform"