* [feature] pure front-matter with no builtin parsers.

[snowyu]

It could get the non-builtin matter and can register your parsers.

cson = require 'cson'
matter = require 'gray-matter/lib'
matter.register ['cson', 'json'], cson.parse.bind(cson)
matter.defalutLang = 'cson'
matter '---\na:123\n---'

matter = require 'gray-matter' # with builtin parsers

• can register the new parser
• separate the builtin parsers to regiter individually
• defaultLang attriubte to matter, default to 'yaml'
• move ./index.js to lib/index.js
• remove builtin parsers on lib/index.js
• rewrite ./index.js to register builtin parsers.

Suggesions and todo:

• matter.read should remove to high level library.

  • to get rid of the fs library dependency.

• register to stringify too.

• remove ugly parsers.requires cache.

  register = require 'gray-matter/lib/parser/parser'
  try
  parser = require '...'
  catch
  throw new Error('you should "npm install xxx" the parser before use')
  register 'xxx', parser

[jonschlinkert]

looks like a great pr! these are some pretty big changes, so I'll need some time to review. I'll come back with some comments as soon as I have a chance

[tunnckoCore]

@snowyu parser system can be handled completely and it's intended to be handled (#12) with https://github.com/jonschlinkert/parser-cache

[jonschlinkert]

closing in light of 2c1b5ce, but I do appreciate the pr. thanks