Add Pagination to User List page

[aeksco]

Add the Pagination component to src/containers/user_list/components/layout.

Consult the src/containers/project_list/components/layout file for a reference implementation

Also - update src/containers/user_list/index.vue accordingly:
This:

  computed: mapGetters({
    fetching: 'user/fetching',
    collection: 'user/filteredCollection'
  }),

Becomes this:

  computed: mapGetters({
    fetching: 'user/fetching',
    collection: 'user/paginatedCollection'
  }),