added some white icons,
changed hardcoded icons to theme attributes,
changed icon_edit_dark to icon_edit_body to reflect icons position,
grey message bubbles in dark theme,
misc

purged ic_action_chat as it wasn't used

preference use_white_background changed to use_green_background, default true

grey chat bubbles darker, text white

replaced all grey600 with black icons and 0.54 alpha attribute

highlightColor in dark grey chat bubble now darker than background

Do not treat Right Alt key as a modifier for key combos