Changes:
* `pathlib` paths support added. ( https://github.com/JIy3AHKO/pyfastmask/pull/8 )
* new function `info_bytes` - get header info from encoded file. ( https://github.com/JIy3AHKO/pyfastmask/pull/9 )
* new function `get_shape` - convenient function to obtain pfm image shape. ( https://github.com/JIy3AHKO/pyfastmask/pull/9 )