Since _ls is now deprecated this is removed in favour of L1, I've also taken the oportunity to replace QStringLiteral and QLatin1String with their shortened form while we're at it.
There are also a few instances where the string literal type has been switch, the general rule being to use the one that matches the function type or value being compared to avoid conversions.
Note this technically won't build for now because of the lack of RoomMember support but I'll push that at the quotient-next branch next.
This is needed as well to get a branch that builds on dev.
If the last active connection is not reachable (server down, keychain problems,
token revoked, etc.), NeoChat currently fails to load at all, with the only fix
being to delete a line from the config file. This is surprisingly hard to fix with
a nice UX as long as we stick to the principle of loading the user's last active
connection automatically.
This patch thus drops that principle; instead, the user is always asked to choose
the connection to continue with.
Previously, some functions that conceptually belong to the connection needed to be in the Controller, since we didn't have a place to put them.
This fixes that by extending the Connection class in a similar way as we extend the Room class.
