Add "deapexer info" to print apex manifest

Since protobuf binary format (.pb) is not human-readable, add 'info'
command to deapexer tool to print APEX manifest from APEX file in JSON
format.

Bug: 143951586
Test: deapexer info com.android.runtime.apex # prints
Change-Id: Ib09e088cb28d651852233bdedd94c2c95be1df67
4 files changed