0.2.1
    Fixed bug when initializing from empty String.

0.2.0
    Add 'borrowed' method
    Bump to 2021 edition    

0.1.3
    Fixed bug when initializing from empty &str.

0.1.2
    Add 'const' constructor Mown::from_str
    Cleaner inner design

0.1.1
    Fixed a bug causing double-free

0.1.0
    Initial release
