Migrate shamu overlay to default config app.

Many of the variables in these overlays were migrated to
CarrierConfgiManager, so the overlay values were migrated into the
default config app (packages/apps/CarrierConfig). Everything no longer
needed here is deleted.

Bug: 20827908
Change-Id: I9ec1c3f240a96746bf02c04c7e96a1ecf6671818
31 files changed