MDL-45394 core_rating Add 'like' button and aggregation method

Signed-off-by: Tony Butler <tonyjbutler@gmail.com>
MDL-45394 core_rating Move styles into separate sheet and add new icons

Signed-off-by: Tony Butler <tonyjbutler@gmail.com>
MDL-45394 core_rating Start to implement alternative UI types

Signed-off-by: Tony Butler <tonyjbutler@gmail.com>