remove dependence on underscore
make keyboard look more like a d3 plugin; extract coupling to state globals
move scale selector towards d3 plugin API; extract coupling to state globals
move fingerboard view towards d3 plugin API
move note grid view towards d3 plugin API
compile multiple jade files
angular

* include angular
* create directives for fingerboard, keyboard
* replace state variable by $scope
* replace d3 dispatcher by $scope.$apply and $scope.$watch
replace d3 scale selector by ng-repeat over pitch constellation directive