fs_config: android_id header generator

Implement an android_id generator that takes the data
acquired from parsing private/android_filesystem_config.h
and generates the android_id friendly name to uid mapping
for consumption in Bionic.

Test: That ls, ps, mkdir, chown, chgrp and services for built
in names work.
Change-Id: I1e55a401be0fca0ad162f8dc1e072e6afde7b927
Signed-off-by: William Roberts <william.c.roberts@intel.com>