Enhance e-mail invitations

- Built-in e-mail template
- More template placeholders

src/main/resources/application.yaml

@@ -1,3 +1,11 @@
+logging:
+  level:
+    org:
+      springframework: "WARN"
+      apache:
+        catalina: "WARN"
+        directory: "WARN"
+
 server:
   port: 8090
 
@@ -18,16 +26,17 @@ lookup:
 ldap:
   enabled: false
 
+firebase:
+  enabled: false
+
 forward:
   servers:
     - "https://matrix.org"
     - "https://vector.im"
 
-firebase:
-  enabled: false
-
 invite:
   sender:
     email:
       tls: 1
       name: "mxisd Identity Server"
+      template: "classpath:email/invite-template.eml"