git-whatchanged: allow other pagers

(but still try to use '-S' if using less)

git-whatchanged

@@ -1,2 +1,2 @@
 #!/bin/sh
-git-rev-list HEAD | git-diff-tree --stdin -v -r "$@" | less -S
+git-rev-list HEAD | git-diff-tree --stdin -v -r "$@" | LESS="$LESS -S" ${PAGER:-less}