fix (directives/grid): add interpolation to grid values
feat (buMain): add event emitter service
fix (bu$directiveCompiler): fix problem causing actual compiler functions to be masked improperly
fix (filters/range): fix problem with numeric strings as values
feat (grid): add ability to promise values + use events for data binding and value loading
fix (directives/grid): remove unnecessary binding from template
feat (directives/grid): add selection to the grid