auto reloading the config

[dakyskye]

What do you want

A flag (-a and --auto-reload) to make dxhd watch the config file passed for changes, and auto-reload that config on change.

Why

To avoid reloading all the dxhd instances/to get changes applied instantly.

Implementation hints

Use fsnotify for it.

[NotUnlikeTheWaves]

Currently looking at using the inotify API that is already provided through syscall so it doesn't create another dependency.

[dakyskye]

Probably reserve -a flag for the future, and use -w --watch for this.
Addition to implementation hints: -w should be ignored if -i is passed.

[dakyskye]

After #39 this can be done easily.