Pull in jquery-ui/draggable

[tilsammans]

This is being used in admin/entries.js

[tilsammans]

Stand by for an updated pull request; I believe it's enough when this is in admin.js.

[coveralls]

Coverage remained the same at 99.032% when pulling 2b12a6b on tilsammans:patch-1 into 44b9d85 on codevise:master.

[coveralls]

Coverage remained the same at 99.032% when pulling 2b12a6b on tilsammans:patch-1 into 44b9d85 on codevise:master.

[tilsammans]

On second thought; this PR fixes the issue and it's at home along all the other jquery-ui imports.

I am leaving this as-is unless @tf tells me otherwise.

[tilsammans]

Error message without this fix:

couldn't find file 'jquery.ui.draggable' with type 'application/javascript'
      Checked in these paths: 
        /Users/joost/Rails/scrollytelling/app/assets/fonts
        /Users/joost/Rails/scrollytelling/app/assets/images
        /Users/joost/Rails/scrollytelling/app/assets/javascripts
        /Users/joost/Rails/scrollytelling/app/assets/stylesheets
        /Users/joost/Rails/scrollytelling/vendor/assets/javascripts
        /Users/joost/Rails/scrollytelling/vendor/assets/stylesheets
        ... (lots more paths)

[tilsammans]

I had a bit more time to investigate this issue, and it was actually caused by an outdated version of pageflow-before-after. Since I switched to master for that one, the correct requires are used for jquery-ui-rails 5.