This patch takes runProcessWithInput out of Dmenu, runProcessWithInputAndWait
out of Dzen, and runInXTerm out of RunInXTerm and collects them in one central
module called Run. This way, other modules may include Run instead of Dmenu
to get what they want without giving the impression of making use of dmenu.
dmenu exits with code 1 when you hit Escape, and I wanna create a contrib that
takes advantage of that.
This required changes in four contribs (Commands, DirectoryPrompt, ShellPrompt,
and WorkspaceDir), and might require changes in users' Configs. Also, I'm not
sure some of the changes I made to the client code are very Haskelly. Would
appreciate input there.
