MusicianInterests       Survey about genre interests of some hobby
                        musicians
MusicianInterestsSmall
                        Small test data of musician, interest and
                        experience study
PositionSurround        ggproto for position_surround()
calc_offset             Calculate offsets for a specific point, in a
                        layer, position
get_offset_table        Calculates offset table for number of maximum
                        overlapping positions
position_surround       Surrounds exact overlapping points around the
                        center
