Set JSON spaces to 2 in development mode
Allowed users to sort field types on buckets

Introduced the Sortable plugin for Mongoose that sorts embedded
arrays as well as introduces the necessary sort field and index.
Client-sided changes are based on #90.
Merge pull request #77 from rubenvereecken/json-spaces

Set JSON spaces to 2 in development mode
Merge pull request #78 from rubenvereecken/issue-108

Allowed users to sort field types on buckets
Fix for sortable when creating a Bucket

There were some issues when editing a Bucket without existing fields
Add gulp tasks.