Improve rooms browser, dialogs and error messages
Error message should be shown when room config update failed.
Room config form should indicate that a password is set.
When a room config has a password, the corresponding password field should show this (it currently is empty, even when a password is used, which is wildly confusing. It also makes it hard to remove the password from a room.
Error message dialog should be sized to display it's content without scrollbars.
Error message dialog should by default show the first part of a stack trace when opened (scroll to top).
Error message dialog should have an optional description text.
The Conference Room browser window should be big enough to display all buttons.
Don't display the word 'null' when there's no description.