Follow symlinks when resolving theme paths.

Closes #4225
- If a theme is symlinked in the themes directory, follow
  the symlink so that the theme object is populated correctly.
- Only do the fallback loading of theme data in the validations
  module if it doesn't exist in config.
Refactor settings and content wrappers to allow smooth overflows and properly show headers on mobile

Closes #4186, Closes #4190, Closes #4150

- Alters markup to allow for correct use of `-webkit-overflow-scrolling: touch;`
- Updates the debug page to use the same markup as the rest of the settings page
- Solve floating tag bar issue by making it absolute, not fixed
Reset password signs the user in

Closes #4196
- Clear confidential info on leaving reset route
- Remove nested password access, because gross
- Also cleaned up some .then(f, h) to .then(f).catch(h) in setup controller
Merge pull request #4230 from novaugust/reset-signs-in

Reset password signs the user in
Merge pull request #4187 from PaulAdamDavis/settings-fixes

Refactor settings & content wrappers
Merge pull request #4226 from jaswilli/issue-4225

Follow symlinks when resolving theme paths.