vrodgom/statmorph: v0.5.0

The "bad measurement" flag now takes values between 0 and 4 (formerly 0 and 1), as explained in the documentation. In summary, a flag of 1 now indicates mild issues with the measurements, while a flag of 2 is reserved for more serious problems. In practice, users of previous versions of statmorph need to know the following when upgrading to v0.5.0:

• The statement flag == 0 has the same effect as before, since a flag of 0 indicates good measurements.
• The statement flag != 1 should be replaced with flag == 0 (to avoid erroneously selecting flag == 2 cases).
• The statement flag == 1 (or flag != 0) should be replaced with either flag >= 1 (to restore the functionality of previous versions) or with flag == 2, which should result in a smaller fraction of "bad" measurements.
• Users who are dealing with a high fraction of "bad" measurements should consider replacing flag == 0 with the less strict flag <= 1 condition.
• The flag_catastrophic property was removed and is now represented by flag == 4 (note that all calculations are aborted when this happens).