ObjFileParser: Moved the parsing of line continuations (backslashes) to the parsing...

ObjFileParser: Moved the parsing of line continuations (backslashes) to the parsing code.

Rather than removing all backslashes followed by newlines from the buffer,
and then parsing it. Handle removing the backslashes as we go. This means
we don't need to erase the backslashes from the buffer (which is O(n))
instead we just skip those characters as we parse the buffer line by line.

This time I've fixed the order of evaluation bug in the call to getFace().