Cleanup of overview page, version button

- Use panels to group rest and rpc controller summaries
- Create "versioning" panel:
  - Has "create new version" button in header
  - default version selection in body
- Remove "create new version" button from version partial; having it on every
  page is potentially dangerous.
Created help dialog for inputs
Merge branch 'feature/ui-cleanup'

- Cleaned up API overview page.
- Moved "new version" button to API overview page _only_.
- Added "help" modal dialog on inputs tab.