Handle MatrixNotFound errors, not UserNotFound

UserNotFound doesn't exist anymore

CHANGELOG.md

@@ -53,6 +53,9 @@ and this project adheres to
 - Fix Python pickling error when trying to redecrypt events after importing
   E2E keys ([#50](https://github.com/mirukana/mirage/issues/50))
 
+- Fix the error message shown when trying to start a direct chat with or 
+  invite a non-existing user
+
 - Handle Matrix 502 errors returned when trying to invite a user with an
   incorrect or unresponsive server in their ID
 

TODO.md

@@ -2,7 +2,6 @@
 
 - fix cursor over field
 - update room highlight when creating new room
-- unknownerror matrixnotfound when creatign directchat
 - keyerror when forgetting room while loading members
 - account order, and verify not adding to config fiel works
 - Refetch profile after manual profile change, don't wait for a room event

src/gui/Pages/AddChat/DirectChat.qml

@@ -44,7 +44,7 @@ HBox {
                     txt = qsTr("Invalid user ID, expected format is " +
                                "@username:homeserver")
 
-                if (type === "UserNotFound")
+                if (type === "MatrixNotFound")
                     txt = qsTr("This user does not exist")
 
                 errorMessage.text = txt

src/gui/Popups/InviteToRoomPopup.qml

@@ -104,7 +104,7 @@ BoxPopup {
                     qsTr("This room rejects users from other matrix " +
                          "servers, can't invite %1").arg(user) :
 
-                    type === "UserNotFound" ?
+                    type === "MatrixNotFound" ?
                     qsTr("%1 not found, please verify the entered user ID")
                     .arg(user) :