Stability: subscriptions, leaflet map wrapper

- Replace session var staticContentReady with staticContentPath
- Create 'subscriptions' api for managing and tracking multiple
  subscriptions (in client.js)
- Subscribe to directory and userDetails in client.js
- Add missing checks to Deps autorun handles
- mapLeaflet: start Deps-autorun handlers in 'created', stop in
  'destroy' and change scope of parameters shared with 'rendered'
Remove previous event modifying behavior
Switch to flex layout

This is pretty much a draft as some features were broken by this
transition
Add missing span
Update to meteor v0.8

- Blaze compatibily issue: assign html 'checked' addribute differently
Remove dedicated ie-support

Dear M$ users:
Sometimes we just have to move up with the times, or live
with bad choices
Reverting meteor to 0.7.2

Unclear issues w/atmosphere packages: Roles, Router.
Waiting until the dust settles
Update bootstrap-3 and roles packages
Add subscriptions integrity sanity check
Organize panel loading order and layout

- Prevent loading of any panel if none is set
- Remove unusued CSS classes from html
Removing auto-locate spinner (better idea?)
Fix multiple leaflet.setView calls issue

- Browser went into high CPU if leaflet.setView was called multiple
  times
- Disable animation when returning from place panel to last center
- Prevent concurrent setView calls
- Create mapProvider.centerSet vs Session var + Deps.autorun