refactor(groupware): add max requests check

* move jmap.request() to jmap.Client.request() and pass the Session
   and a Logger to introduce checking the number of methodCalls within a
   request not exceeding the limit of the Session, as well as error
   handling and logging there instead of in each caller

 * a few bugfixes:
   - add a few missing Send() calls in logs
   - correct the response tag matching for
     GetMailboxChangesForMultipleAccounts
   - fix typo in Identity.ReplyTo json serialization rune
   - fix response tag in pkg/jmap/testdata/mailboxes1.json after
     changing them to be prefixed by the accountId

pkg/jmap/testdata/mailboxes1.json

@@ -116,6 +116,6 @@
 			}
 		],
 		"notFound":[]
-	},"0"]
+	},"a:0"]
 ], "sessionState":"3e25b2a0"
 }