more gentle error handling

[podhmo]

26

This is ad hoc fix.

• adding InvalidTypeIncluded (exception)
• more strict error handling (don't catching Exception)

from semver import max_satisfying

print(max_satisfying([b"1.0.0"], "1.0.0"))
# semver.InvalidTypeIncluded: must be str, but b'1.0.0'

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(typing (#27) is more better, conceptually?)