Improved template rendering, made columns sortable, loading columns dynamically from elasticsearch
Made a start on UI and plumbing for adding sources to columns

* Updated taproot/subscriptions with a bunch of new features and bugfixes
* Added bean.js
* Created http.js, a minimal syntatic sugar library for XMLHttpRequest + Promise
* Created basic source-adding UI for columns, where adding a new URL subscribes (or resubscribes) to that URL and initiates a crawl, also adding it to the column’s sources list with relevant profile data if it exists.