Parse+React 0.6.0

[andrewimm]

The 0.6.0 release will be focused on adding functionality needed by mobile applications.

• Allow count query subscriptions (Implement an equivalent for Parse.Query.count() #88)
• Let the state of the Object Store be saved an initialized. This will allow applications to cache object state for offline functionality. This might be further extended

Additionally, there will be some code reorganization tasks.

• The query matching engine (the piece of code that determines whether an object matches a Parse query) will be broken out into its own npm module, so that it can be maintained independently and can be used by other projects.
• We will move subscription / observable functionality into the upcoming Observable-React project. This will make sure that the observability APIs we originally pioneered in Parse+React stay in sync with community development.