load_nfl_rosters pre- and post-2002 columns not matching

Getting an error from:

`sdv.nfl.load_nfl_rosters(list(range(1999, 2005)))`

Leading to the error:

`ShapeError: unable to append to a dataframe of width 30 with a dataframe of width 36

The columns that don't exist in the earlier seasons are:

`
ngs_position
week
game_type
status_description_abbr
football_name
draft_number
`