Filter Meta Bar

Summary:
* adds "Add to Set" and "Export" buttons to filter meta bar

Fixes T1096

Test Plan: * confirm buttons and test responsive views

Reviewers: shadowhand

Reviewed By: shadowhand

Subscribers: brandonrosage, spaudanjo, sebm90, digitalafrican, srutto, dkobia, rjmackay

Maniphest Tasks: T1096

Differential Revision: https://phabricator.ushahidi.com/D501