Add Tab components

Closes #3937
- Add ghost tab components
- Remove extra container div from Application view
- Move right-outlet viewing logic to application level
- Prepare PSM.hbs for tabbing
Revert "update CodeMirror 4.5.0"
Adjust morgan call to avoid deprecation warning

No Issue
- Change the invocation of the morgan logging package to
  conform to the new function signature introduced in
  morgan 1.2.0.
Merge pull request #4042 from novaugust/psm2-tabs

Add Tab components
Merge pull request #4071 from TryGhost/revert-4022-master

Revert "update CodeMirror 4.5.0"
Fix ghost-ui reference

fixes #4072
- Correct reference to ghost.min.css
Merge pull request #4076 from halfdan/4072-404page

Fix ghost-ui reference
Merge pull request #4075 from jaswilli/morgan

Adjust morgan call to avoid deprecation warning
Fix several tiny CSS bugs

Closes #4050

- Full-width invite user modal button
- `<select>` can be focused in Firefox
- Increase size of background images for avatars
- Add `-moz-osx-font-smoothing: grayscale;` to icons
Correctly close PSM

closes #4077
- Swap CSS toggling for new PSM closing method
Merge pull request #4079 from halfdan/4077-close-psm

Correctly close PSM
Merge pull request #4053 from PaulAdamDavis/css-bug-fixes

Tiny CSS bug fixes
Change HTML email link to hide token

closes #3305
- Hide token in HTML email
Naming cleanup

closes #4069
- Rename everything from camelCase to lowercase + dashes
- Remove usage of `server`, `app` and `instance`
Meta data screen

closes #3939
- Add Seo Tab component to PSM
- Add new gh-blur-textarea component
- Refactor blur-input to use new text-input mixin
Merge pull request #4066 from halfdan/3939-psm3-meta

Meta data screen
Fixes sass:compress

no ref
- Use absolute path for compress/sourceMap
Merge pull request #4092 from halfdan/fix-sass

Fixes sass:compress
Merge pull request #4081 from halfdan/3305-derp

Change HTML email link to hide token
Validate and properly color letter count.

fixes #4087
- Adds correct validations for meta_title/meta_description
- Adds correct coloring of letter count