Merged in most of the current common prediction changes
that were under the #if CONFIG_COMPRED option.

Change-Id: If4e6f61dbe7b86dd449f6effbe93b5eb7e893885

Moved the prob_dualpred[] sturcture to common.
Created common prediction entry for Dual flag.

Change-Id: I9ac3d128bae6114f09e5c18216d4b95cf36453d5

Extended prediction and coding of reference frame where
a subset of options are flagged as available at the segment level.

Updated copyright notices.

Switch to SAD in mbgraph code as SATD problematic for the
foreground and background separation as it can ignore large DC shifts.

Change-Id: I661dbbb2f94f3ec0f96bb928c1655e5e415a7de1

This function adds the common prediction modules,  some data structures
and a config option but does not use them.

It also corrects a bug in clearing down  the MODE_INFO border and introduces
a new element that indicates if an entry corresponds to an "in image" macro block
or is part of the border.

Change-Id: Ib69eec0876173ebe9d1de9df9537d0b2447702e0