Improve some docs, fix some debugging.

- Add docs to Binder, Messenger, ResultReceier to explain their
  relation (or lack there-of) to process lifecycle.
- Clarify some aspects of process lifecycle for services.
- Fix help text of am command.
- Fix per-package dumping of battery stats to not include history.
- Fix per-package dumping of proc stats to only include aggregated
  and current stats and fix some formatting.
- Fix per-process dumping of meminfo to have an option to interpret
  the input as a package, so including all processes that are
  running code of that package.
- Fix top-level per-package debug output to correctly include all
  of these improvements and give them a little more time (10s) to
  complete for timing out.

Change-Id: I2a04c0f862bd47b08329443d722345a13ad9b6e2