Fix an issue with no default for some $head_config params
Updates themes, including fallback, to comment out unneeded params (since they are defaults)
Now that we've fixed $head_config defaults, we should make primer_css true instead of false because of how it has acted
Now that we've fixed $head_config defaults, we should make primer_css load first (if not set) because of how it has acted
Now that we've fixed $head_config defaults, we should make primer_css load first (if not set) because of how it has acted (logic fix to prevent warning)
Merge branch 'develop' into bootstrap3dave