{{gh-path}} Handlebars helper, returning paths

- Uses utils/ghost-paths to resolve paths
- {{gh-path}} or {{gh-path ‘blog’}} for Ghost’s root (mysubdir/)
- {{gh-path ‘admin’}} for Ghost’s admin root (/mysubdir/ghost)
- {{gh-path ‘api’}} for Ghost’s admin root (/mysubdir/ghost/api/v0.1)
Incrementing hard limits for Meta title and Meta description

closes #4124
- incremented values for client-side validation for Meta title and Meta description
- changed error messages to display the maximum number of characters.
Disable horizontal scrolling in right outlet

Closes #4131

- Adds `overflow-x: hidden;` to `.right-outlet`
Rewrite publish bar markup

Closes #4123, closes #4114, references #4105

- Rewrite to use flexbox for über mobile goodness
- Fixes tag suggestions (using the new dropdown style)
- Fixes vertical alignment
Merge pull request #4136 from PaulAdamDavis/fix-right-outlet

Disable horizontal scrolling in right outlet
Update icons
Merge pull request #4137 from JohnONolan/icon-refresh

Update icons
Updated dropdown component style
Merge pull request #4128 from PaulAdamDavis/fix-tags-input

Rewrite publish bar markup
Merge pull request #4126 from mattiascibien/issue-4124

Incrementing hard limits for Meta title and Meta description
Merge pull request #4139 from JohnONolan/dropdown-refresh

Updated dropdown component style
Static page and feature options in new PSM

closes #4109
- Add featured option
- Move static page/featured to other place
- Change wording on static page
Merge pull request #4111 from halfdan/4109-psm

Static page and feature options in new PSM
Merge pull request #3824 from felixrieseberg/iss3718-2

{{gh-path}} Handlebars helper, returning paths
Open user menu on hover

References #4007

This is purely WIP, for experimentation.