Enhancement: spec for the status quo
Update: less whitespace for easier matching
Enhancement: add group attribute for consistency
Refactor: refactor nginx.conf generation into defintion

 * definition accepts parameters to do certain things
 * unifies how the configuration is written across recipes
Refactor: move definition into LWRP

 * adjust nginx-lb and nginx-app recipes and specs
 * introduce a matter for notification matching
Enhancement: make LWRP send notifications
Merge pull request #436 from till/t/refactor-nginx-conf-generation

T/refactor nginx conf generation