Swipe events

[richsilv]

• Adds a central subs manager using meteorhacks:subs-manager to cache subscriptions.
• This allows the use of a global universal-loader package to display a spinner whenever we are waiting on subs.
• Adds swipe interactions which move the page naturally and trigger a return to the parent page (as defined in the router) whenever we swipe back.
• Refactors field-lookup to simplify it and allow the user to pass a save method so that an interaction within the component (like hitting enter in an input box) can trigger a save.
• Adds and corrects loading spinners throughout the site.

[alanshaw]

:eyeglasses:

[alanshaw]

This all looks good and seems to work well. There are 30 files in this PR though and changes unrelated to swipe events (subs manager, universal loader, etc.). In the future please split these into multiple PRs that are easier to review and more focused on a single set of functionality.