Don't bother trying locate a full path if the Command looks like a path

Fixes #2

src/arun-handlers.adb

@@ -84,6 +84,12 @@ package body Arun.Handlers is
       Full_Path :  aliased constant String := L.Find_Full_Path (Command);
    begin
 
+      if Command (1) = '/' then
+         -- If the command starts with a slash, it's likely already a full path so
+         -- just try to execute it!
+         L.Execute (Command, Slices);
+      end if;
+
       if Full_Path /= "" then
          Put_Line ("Should Execute: " & Full_Path);
          L.Execute (Full_Path, Slices);