openshift.ks: Validate settings

set_defaults: Check for unrecognized or empty settings and abort if one is
found and verify that the list of components to install includes only valid
components.

This commit fixes bug 1097910.
Merge pull request #340 from Miciah/enterprise-2.1/openshift.ks-validate-settings

openshift.ks: Validate settings  
Bug 1097910 has been verified