Fix contour alignment in VizEquiMap.R

See merge request !32

'label_scale' -> 'bar_label_scale', 'tick_scale' -> 'bar_tick_scale', 'extra_margin' -> 'bar_extra_margin' in ColorBarContinuous and its calls in VizEquiMap, VizLayout, VizRobinson and VizStereoMap

# Conflicts:
#   R/VizEquiMap.R

Caption feature for VizEquiMap.R

See merge request !27