Export script updates and improvements.
Export script updates and improvements.

* Fix some broken package names
* Support ArrayMap
* Require the user to supply the jetpack changeid they're syncing, and
  write it into the destination dir so we can figure out what platform
  is synced to.

Bug: 162450968
Test: Export
Change-Id: I58c4ab23826111bc38b4890a955ccec4f84cfd98

AndroidX/androidx,AndroidX/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx,androidx/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,AndroidX/androidx,AndroidX/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx,AndroidX/androidx,androidx/androidx,androidx/androidx