0.5.0

• Strict optional typing is now enforced (#68)
• Fixed deduplication of tag names (#69)
• Sources and patches can now be removed by number (#69)
• Number of digits in a source number is now expressed the same way as packit does it (#69)
• Empty lines are now compressed when deleting tags (#69)
• Added convenience property for getting texts of tag comments (#69)
• Added convenience method for adding a patch (#69)