Fix of ticket #98 on incorrect derivation of chroma-tree split context. Patch provided by adam.wieckowski@hhi.fraunhofer.de

This is JVET L0054 MMVD code.
MACRO is JVET_L0054_MMVD.

See merge request !26

Squashed commit of the following:

commit d9b44c28
Author: seungsoo <ss00.jeong@samsung.com>
Date:   Fri Oct 26 08:28:35 2018 +0900

    code update ( reflection )

commit 1fd1b434
Author: seungsoo <ss00.jeong@samsung.com>
Date:   Thu Oct 25 10:59:22 2018 +0900

    code update ( reflection of commented things )

commit 3befe26e
Author: seungsoo <ss00.jeong@samsung.com>
Date:   Wed Oct 24 13:18:27 2018 +0900

    JVET_L0054_MMVD is uploaded.