Handle error case for creating a new character.

Most likely cause of this is trying to create a character that already exists.
set up params for /names route
validation for id and type parameters in route
Support retrieving all characters and relationships, separated by chapter.

On GET /api/names/
Add API support for filtering by ID and relationship types
change type-only query to return only relevant characters
Update reindexLinks to take data organized by chapter
Update controller method, getAll, to store data organized by chapter with reindexed links
Update http request route for getAll to /api/names/type
Add express-params to package.json
Change getChar route to not include chapter id
Update getAll to receive id and type, remove getChar and getRelsOfType
Invoke getAll factory method with parameters for id and type, remove getChar and getRelsOfType
Merge pull request #14 from valiantvu/filter-relationships

Refactor requests to be parameterized by ID and Type