Items edit: remove warnings about not all types being supported.

It's not really true anymore, we support essentially all of them, and if
we are missing any, we want it to be reported so we can fix it.

src/Calendars/EventEdit.tsx

@@ -413,11 +413,6 @@ export default class EventEdit extends React.PureComponent<PropsType> {
               Save
             </Button>
           </div>
-
-          <div>
-            Not all types are supported at the moment. If you are editing a contact,
-            the unsupported types will be copied as is.
-          </div>
         </form>
 
         <ConfirmationDialog

src/Contacts/ContactEdit.tsx

@@ -596,11 +596,6 @@ class ContactEdit extends React.PureComponent<PropsType> {
               Save
             </Button>
           </div>
-
-          <div>
-            Not all types are supported at the moment. If you are editing a contact,
-            the unsupported types will be copied as is.
-          </div>
         </form>
 
         <ConfirmationDialog

src/Tasks/TaskEdit.tsx

@@ -481,11 +481,6 @@ export default class TaskEdit extends React.PureComponent<PropsType> {
               Save
             </Button>
           </div>
-
-          <div>
-            Not all types are supported at the moment. If you are editing a contact,
-            the unsupported types will be copied as is.
-          </div>
         </form>
 
         <ConfirmationDialog