Reduce OMS start time

This change attempts to reduce the amount of time initializing the
OMS. The change:
1) Reduces the amount of time between subsequent attempts to connect
   to the idmap2d service when it is not alive.
2) Caches package infos retrieved from getOverlayPackages
3) Caches the crc of the android package to preventing having to
   retrieve it for every overlay package targeting the framework

This chance reduced OMS start up time from ~500ms to ~100ms on a
Pixel 3. If the idmap2d service is running when system sever starts
then start up time will be around ~70ms.

Bug: 151481016
Test: adb shell stop && adb shell start && [capture trace]

Change-Id: I6137c385baf099413b62e98557419fffb9fd2d93