Add Gulp tasks

Add gulpfile with tasks for linting, building and watching
Add gulp dependencies to package.json
Add dist directory to .gitignore
Add compilation instructions to README
Add test task

Add test task to gulpfile
Add dependencies for using mocha and chai
Add test sources as a variable
Add test task as dependency for several tasks
Add access-token/cipher-aes-256-gcm module

Add module for AES-256-GCM encryption
Add module dependency to package.json
Add mocha tests
Add access-token sources to coffee sources
Add test task to README
Remove key derivation logic from module

Module aes-256-gcm should receive a buffer as the key
Add KEY_SIZE as export
Refactor tests to reflect change
Add tests for key validation
Rename required module in test
Add AccessTokenManager

Add AccessTokenManager as main module for access-token
Add module dependency to package.json
Add mocha tests
Merge branch 'access-token' into develop
Reformat sources definition in gulpfile
Add facebook-auth sources to coffee sources
Add FacebookAuthProvider

Add FacebookAuthProvider as main module for facebook-auth
Add mocha tests
Rename coffeeSources to nodeCoffeeScriptSources
Merge branch 'facebook-auth' into develop
Rename nodeCoffeeScriptSources to nodeSources
Change dist literal to variable in clean task
Add information about CoffeeScript installation

Add “Installing CoffeeScript” section
Add missing link to CoffeeScript homepage
Reformat text
Add dynamodb-datastore sources to nodeSources