added behat features to create tokens with scope logic
added to check scope existence
added to check if a scope is allowed by the client
added scope collection
fixed checking allowance of several scopes
added default client scope
Merge branch 'master' into scopes_logic

Conflicts:
	src/Akamon/OAuth2/Server/Behat/FeatureContext.php
refactorized acceptance scope tests and added to use custom token grant type processors
added to make optional refresh token repository in storage
added travis config file
Merge pull request #5 from Akamon/scopes_logic

[WIP] Scopes logic when creating tokens