Convert Node/Content types to CMI

[jenlampton]

Node types need to save their settings into a config file.

For reference, here is the parallel issue from drupal.org

[quicksketch]

I'm going to start working on this one, as our most important CMI conversion not yet underway.

[quicksketch]

Things are coming along quickly here. We've got tests 98% passing already: https://github.com/quicksketch/backdrop/compare/171/node_config

Converting node types actually seems to be very straight-forward. They're well contained and the new approach makes managing settings significantly easier than the 20-50 variables per content type we had previously. Now all settings will be stored in a single node.type.[type_name].json file, with modules responsible for cleaning up their settings on uninstall, but not on deletion or renaming of node types. A much easier system to manage overall.

This doesn't include converting fields yet. I think we'll need to convert Taxonomy terms/vocabularies and Users to CMI first, then we can move on to fields.

[quicksketch]

This PR is ready to go (IMO) at backdrop/backdrop#507.

The conversion to CMI is pretty straight-forward. I love being able to delete all the per node type variables. This PR also includes a number of updates to our JS files that deal with vertical tabs, since the form elements for a number of options have changed their names.

[quicksketch]

Merged in backdrop/backdrop#507. Yay! On to Taxonomies and Roles.