0.2.6 - More robust desktop launching

Fallback order
 - `dex`
 - `gio`
 - `exo-open`
 - `gtk-launch`
 - linch manual launch

It also checks gtk-launch to make sure it actually launches cause
APPARENTLY it doesn't know subdirectories exist???

I know there's others like `kde-open` but I couldn't make them work
seamlessly as a subprocess so too bad