JSONSerializer recognises keyForAttribute/keyForBelongsTo if defined
Add info on sending underscored JSON for create/update operations

In 0.13 the REST Adapter would send underscored JSON for create/update
requests.  Beginning in Beta 1 the REST Adapter sends camelized JSON.

This PR updates TRANSISTION.md to show how to get back to underscores.
Add info about getting underscored root object in create/update requests.

In 0.13 the REST Adapter would send underscored versions of multi word
model names as the root element.  Beginning in Beta 1 the REST Adapter
sends camelized root object.

This PR add info to TRANSITION.md about how to get back to underscored root objects.
Add test for custom typeFromRoot
change modelTypeFromRoot to typeFromRoot to match pathFromType.
Rename adapterForType - adapterFor to match serializerFor
Merge pull request #1251 from bradleypriest/rootFromType

Add test for custom typeFromRoot
Merge pull request #1244 from bradleypriest/keyFor

JSONSerializer recognises keyForAttribute/keyForBelongsTo if defined
Merge pull request #1252 from bradleypriest/renaming

Renaming a couple of hooks
fix test after renaming
Merge pull request #1255 from bradleypriest/test

fix test after renaming
Merge pull request #1250 from jagthedrummer/jeremy/underscore-root-json-serializer

Add info about getting underscored root object in create/update requests
Only get store if it's needed

I'm trying to dig into #1243 and the inconsistency between belongsToWillChange and belongsToDidChange was irritating me. :)
Added missing resovler definition on DS.ManyArray
Added test for missing resolver bug
Fix: Missing semi-colon in test
Simpler example for JSON requests
Fix docs
Merge pull request #1262 from bradleypriest/docs

RESTAdapter actually expects camelcased keys by default
add inflector rule addition DSL

(@hjdivad / @stefanpenner)