Fix three-word command names

Command names like MakeCacheTree weren't coming up with hyphens between
every word, so they read "debug-make-cachetree" rather than the
expected "debug-make-cache-tree".  On each lowercase character reset
the lastWasDash flag so the next uppercase will insert a hyphen before
the next word.

Change-Id: I539fabb339e60896165619c307dec71e3317b0d8
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>

org.eclipse.jgit.pgm/src/org/eclipse/jgit/pgm/CommandRef.java

@@ -93,6 +93,7 @@ public class CommandRef {
 				s.append(Character.toLowerCase(c));
 			} else {
 				s.append(c);
+				lastWasDash = false;
 			}
 		}
 		return s.toString();