OneShot: Allow chaining one-shots

When another one-shot key is pressed, reset the timer, and handle it as if
starting anew, but without cancelling any previous one-shots. This allows one to
chain one-shots together.

Fixes #3.

Signed-off-by: Gergely Nagy <algernon@madhouse-project.org>

src/Akela/OneShot.cpp

@@ -179,6 +179,13 @@ namespace Akela {
             setSticky (idx);
 
             saveAsPrevious (mappedKey);
+          } else {
+            Timer = 0;
+
+            setOneShot (idx);
+            saveAsPrevious (mappedKey);
+
+            activateOneShot (idx);
           }
         }
       }