Externalize Resttemplate from TrelloImpl
Add support for HttpClient 4.2.x
TrelloHttpClient encapsulates HTTP error on an TrelloHttpException
Rename HttpClient to ApacheHttpClient
Add private method getEntityAndReleaseConnection
Add a new constructor on ApacheHttpClient
Move *HttpClient into http package
Add an AbstractHttpClient
Refactor constructors on ApacheHttpClient
Add support for AsyncHttpClient