Wiring up workspace published/unpublished/all posts views (Rough)

- Add routes for posts/all, posts/unpublished, posts/. Routes for these
will set status
filter and then render the normal ‘index’ controller action.
- Hide tasks and tutorials in workspace menu
- Add PostCollection.setFilterParams() function which handles combining
filters
with paging params and reloading if filters change.
Improve handling of frontend 'view' switching: map, list, full

- Move handling of views for home layout (map, list, search) into
HomeLayout
- Maintain the 'view' as a state on the Home Layout. This means we can
return to the last ‘view’ the user selected, not always back to ‘full’
post view.
- Add HomeLayout.setViews() that lets you set which views (map, list,
search) to render
- Add onClose() callback to MapView to destroy the leaflet map object
when the view is hidden.
- Link ‘Full’ view to /view/full since index now renders which view was
shown last
- Not loading MapView in Controller directly so we have to require
  it for postDetail
Avoid triple reload of posts during paging, etc

Post list was loading post 4 times when each page changes.
This was because the ‘remove’ event is fired for each post
in the list as its replace. We’re moving the fetch() call to
PostItemView.deletePost() since that when we actually
wanted this reload.
Pass posts filter params to map view

Map view now grabs filter params from collection and passes them
to the GeoJSON api when loading posts.

- Moved mapView data url handling to MapView.getDataUrl()
- Add PostCollection.getFilterParams() api to grab filter params
- Pass filter params to jquery.ajax data param
Reset posts filters in 'index' controller

Reset the posts filters when user hits index. Stop calling this
controller internally
on workspace views to avoid accidental resets.
Fix rerendering the home layout

Only call show(homeLayout) when its not already visible. This avoids a
heap
of extra JS work and avoid we’re jumpy-ness.
Avoid using global App.Collections.Posts in HomeLayout

Pass post collection when creating home layout instance, use that for
child views.
Trigger map reload when post filters change.
Fix list view not hiding the map properly.
WIP
Improve/update handling on active view and workspace menu itmes

Wire active menu item in workspace menu to 'page:change' events
Wire active view to ‘view:change’ events
Merge pull request #171 from ushahidi/workspace-posts-views

Wire up workspace views for all posts, unpublished posts, published posts