update(kpis.svc guarding): ImpacDeveloper.isEnabled
update(kpis.svc guarding): ImpacDeveloper.isEnabled

Update needed for removal of http.defaults basic auth,
due to replacement with http interceptor.

Previous implementation of guarding for kpi's #show & #create
methods where checking for $http.defaults common headers for
basic auth. Now that the ImpacDeveloper service is implemented,
the #isEnabled method is more appropriate.

xaun/impac-angular,maestrano/impac-angular,cesar-tonnoir/impac-angular,cesar-tonnoir/impac-angular,xaun/impac-angular,maestrano/impac-angular