RFC: Global atom-configuration

[joelgriffith]

This plugin is great when working on projects that might potentially be consuming queries from disparate GraphQL servers, or when working with other developers that use atom, however the .graphqlrc convention tends to lose its luster when working on larger projects with a more diverse developer base.

I propose that a new, atom-based setting be exposed that allows users to define a "global" HTTP server or JSON file for building the autocomplete. This way atom users can continue to enjoy the benefit of this plugin without burdening project maintainers with another file.

With this change in mind, when the plugin begins, it will:

• Look for a .graphqlrc file with the appropriate schematic, as defined in the README.
• Failing that, will try and look for a atom-config setting for it to operate off of.

Open Questions:

• Is it possible to have a per-project atom setting?
• When do we want to communicate failures? (IE: if a .graphqlrc is present, but doesn't conform to the shape as outlined in documentation).