command line options

[absoluteshitlord]

Would be nice to have some options for starting vaccine from terminal.
e.g. vaccine --board g to start up on /g/ . This would be nice for keybindings.

[Prince781]

https://valadoc.org/gio-2.0/GLib.Application.command_line.html
https://valadoc.org/gio-2.0/GLib.Application.handle_local_options.html

At first glance it looks like this would be easy to implement. One consideration: vaccine is currently a single-instance application. If vaccine is already running when it is executed, then either we should pass the command line flags to the primary instance of vaccine (to trigger a change) or ignore them altogether.