Warning messages for comment lines if the first piece of data has multiple characters

[bfrymire]

The header of an OBJ file that was generated by Meshlab will start with comments about the file. For example:

####
#
# OBJ File Generated by Meshlab
#
####
# Object voronoi.obj
#
# Vertices: 763
# Faces: 88
#
####
mtllib ./voronoi.obj.mtl

The lines with #### are comments, although will be output as warning messages:

DotobjClassGroup(): Created group "__dotobj_group__"
DotobjModelLoad(): Warning! "####" is not recognised. (ln=1)
DotobjModelLoad(): Warning! "####" is not recognised. (ln=9)
DotobjModelLoad(): Warning! "####" is not recognised. (ln=21)

[JujuAdams]

Not something I'll be fixing in the short term. Feel free to author a PR and I'll review (and maybe merge) that.