lispy.el (lispy-kill): improve

* lispy.el (lispy-push-into-set): Remove.
  (lispy-mark-right): Fix.
  (lispy-mark-left): Fix.
  (lispy--out-forward): Don't indent when `lispy-ignore-whitespace'.
  (lispy--insert-or-call): Fix doc.
  (lispy-define-key): Update.

* lispy-test.el (lispy-kill): Add test.
lispy.el: "h"/"l" now move region, not code.

Now, to move a marked sexp out of its parent list up/down
instead of using "h"/"l", use "oh","ol",
i.e. `lispy-other-mode' must be called.

Plain "h"/"l" will now only change point and mark, not code.