Deprecate oc_isadmin and move OC.isUserAdmin() to the bundle

core/js/dist/main.js

core/js/dist/main.js.map

core/js/js.js

core/js/tests/specHelper.js

core/src/OC/admin.js

core/src/OC/index.js

core/src/globals.js

lib/private/Template/JSConfigHelper.php