fix LoadOBJFile features initial index

[brccabral]

Hi,
When parsing a 'f' line the first non junk character was skipping resulting in a crash when loading .obj files.

f 2/3 4/7 1/5

The number 2 was skipping.

Checking for nTokenCount first solves the issue.

In the CGE tutorial there was no size() check. I kept it because maybe there is a scenario where it is needed.

Thanks,
Bruno