Abstract out base Model and Collection

This handles parsing the `_links` response data and adding them to a
local `urls` object.
Update GET param for querying the fields and concepts endpoints
Add local sub-collections to ConceptCollection

This differentiates between _queryable_ vs. _viewable_ concepts
for the query and results views, respectively.
Replace ConcepForm field form logic with FieldFormCollection

The collection handles rendering each field's control and the first
available chart. This logic may need to be improved or make it more
option-drive.
Add support for multi-key/value context node lookups

Empty lookups return false, only if each key/value pair match does it
return true.
Add option for creating the representative node if lookup fails

Supports the common 'get or create' use case if `options.create` is true
Update Field and Concept models with base models

Replace Concept.fields array with a collection. This enables binding
events, which further enables lazily loading the Concept's field data
only when it's initially _focused_.
Add two additional targets for creating a source dist vs. uglified
Remove SESSION_OPENED subscriber for FieldCollection

The field data is not used directly by any UI elements and does not
need to be loaded. Furthermore, each Concept handles loading it's
specific set of fields so this collection would be redundant.
Update package.json, add bower.json
Add contributors
Add compatibility section to README
Update install section for NPM and Bower repos