PLT-6965 jira integration (plus plugin scaffolding) (#6918)

* plugin scaffolding / jira integration

* add vendored testify packages

* webhook fix

* don't change i18n ids

* support configuration watching

* add basic jira plugin configuration to admin console

* fix eslint errors

* fix another eslint warning

* polish

* undo unintentional config.json commit >:(

* test fix

* add jira plugin diagnostics, remove dm support, add bot tag, generate web-safe secrets

* rebase, implement requested changes

* requested changes

* remove tests and minimize makefile change

* add missing license headers

* add missing comma

* remove bad line from Makefile

webapp/routes/route_admin_console.jsx

@@ -46,6 +46,7 @@ import LicenseSettings from 'components/admin_console/license_settings.jsx';
 import Audits from 'components/admin_console/audits';
 import Logs from 'components/admin_console/server_logs';
 import ElasticsearchSettings from 'components/admin_console/elasticsearch_settings.jsx';
+import JIRASettings from 'plugins/jira/components/settings.jsx';
 
 export default (
     <Route>
@@ -159,6 +160,10 @@ export default (
                 path='webrtc'
                 component={WebrtcSettings}
             />
+            <Route
+                path='jira'
+                component={JIRASettings}
+            />
         </Route>
         <Route path='files'>
             <IndexRedirect to='storage'/>