Stop sending welcome message

Even for its intended use case, it often confuses more than it honestly helps.
Clean up many fromString "" to s""
Fix cheogramDiscoInfo

XML attributes do not have an explicit namespace unless prefixed.
Prevent openBinaryFile: invalid argument (File name too long)
Use oldstable in CI for now, since prod does and my desktop does

And new cabal is incompatible
Support xdata-validate:open for list-single

This allows the user to enter any item the matches the datatype as well as
choose from the list.
Put cheogram provided commands last
Send presence request after register
Add cheogram/pstn identity to disco and caps when there is a sip backend
Do not log or record in the DB on non-MUC presence
Show possible route for confused users who came from web register
Don't accept gateway JID with node or resource

Most of the code assumes a gateway JID is a bare domain.
Enter Gateway vs Enter Gateway JID

To reduce the chance than anyone thinks their JID should go here.
Increase IQ Timeout

Sometimes steps in the registration flow can take longer than 5 seconds.
We're increasing the timeouts here because these aren't errors, and it
will make signup much smoother to have this work.
Do not show command error on successful cancel
Do not show help text after cancel
Fix spelling on status=canceled and add a note
Tell the user what the actions are when waiting at a note
Loosen dhall constraint