Contacts: hide Memory Status screen for now

This screen doesn't really provide any useful information at the moment.
It was meant to display SIM card status, but we do not have a SIM
contact provider in place to retreive this info.

So it just displays total contact counts for each account.

Change-Id: I0a8bffeb7712f83a6e1768a0f9c8effcfec46996
Signed-off-by: Roman Birg <roman@cyngn.com>