In the previous description of the CamVid format, the filename for the label was 'labelmap.txt', but the correct filename is 'label_colors.txt'.

Therefore, in this proposal, I fixed 'labelmap.txt' to 'label_colors.txt'. Also, I added the comment about 'color (RGB) value is not necessary'.

Added a description about 'Fix filename for label in CamVid format'

…color information)

Add example code about label_colors.txt without color information.

->
# label_colors.txt (without color value type)
# if you do not manually set the color for labels, it will be set automatically:
# label
Void
Animal
Archway
Bicyclist
Bridge