quick script to do version bumps

bump.py

import sys
import numpy as np

file_name = 'trimesh/version.py'

if __name__ == '__main__':
    with open(file_name, 'r') as f:
        text = f.read()

    split = text.split("'")
    v = split[1]
    assert v.count('.') == 2
    vs = np.array([int(i) for i in v.split('.')])

    # -0: major bump
    # -1: minor bump
    # anything else: patch bump
    if '-0' in sys.argv:
        which = 0
    elif '-1' in sys.argv:
        which = 1
    else:
        which = 2

    vs[which+1:] = 0
    vs[which] += 1
    split[1] = '.'.join(vs.astype(str))
    new = "'".join(split)

    print('was: {}\nnow: {}'.format(text.strip(), new.strip()))

    with open(file_name, 'w') as f:
        f.write(new)