sdcard: Allow building as a static library

 * Split main() out in order to allow linking with a multi-call
   executable such as recovery.

Change-Id: I3325135e47e4dd5af3912f5ce67ec64007d54a63
init:define BOARD_CHARGING_CMDLINE parameters
Conflict init/Android.mk
Revert "init.rc: Create /storage mountpoint so Dalvik can mark as slave in zygotes"

No longer needed as Dalvik no longer marks /storage as slave in zygotes.

This reverts commit 4a8f70d11b225fbf56aca6e494f4de35fc727dc7.

Change-Id: I0bfb86f2cc10ccdc10daa7419ac4d252c8dfbae8