fix property enforcement
Merge pull request #1799 from 9rnsr/enforceProp

fix property enforcement
Remove modules crc32 and std.md5 which had been deprecated by 6ff6adc5bf7d13b33e27985c53377cd20d7648e6
Merge pull request #1800 from Geod24/remove-deprecated-modules

Remove deprecated crc32 and std.md5