Fix test_utils.compatible_with

[speleo3]

Fixes #370

Solution is similar to

pymol-open-source/testing/testing.py

Lines 87 to 94 in 86ff2c3

	def tupleize_version(strversion):
	r = []
	for x in strversion.split('.'):
	try:
	r.append(int(x))
	except ValueError:
	break
	return tuple(r)

[JarrettSJohnson]

Thanks. This uncovered some issues; I'll double check these on other machines.