Added support for refreshing the device list, marking current device with a checkmark instead of a lock

Fixes for pasting images, especially under windows where the image mime type detection doesn't work as expected

Fix --help and --version command line options when Nheko is already running. Also adds an info message when it sends a URI to another instance

* Added a text field that allows choosing custom homeserver in "Room directory" dialog.

* Moved "Choose custom homeserver" text field to the right and shrinked it to 30% of "Room directory" dialog's width.

* Adding "server_name=" when needed when joining room.

When joining room that is hosted on a different homeserver than
the account is registered on, the request fails. In such scenario
the server has to be explicitly mentioned in a server_name URL
parameter. More info here:
https://matrix.org/docs/spec/client_server/r0.6.1#post-matrix-client-r0-join-roomidoralias



* Minor fix: intentation (4 spaces -> 8 spaces)

Co-authored-by: Patryk Cisek <patryk@cisek.email>

- Fixes scrolling to an event not being reliable
- Adds new /goto command that can open URLs, go to events, or go to message indexes.
- Refactored ChatPage::handleMatrixUri() to contain the handling originally in Nheko::openLink(), and makes it return a boolean based on whether the URL was handled internally or not.

There is not really a reason to stop tracking them, just because the
server says so. We might still want to show a users profile, etc.