allow passing scalar numbers

[mathause]

The following currently throws an error (TypeError: 'int' object is not iterable):

import filefinder
ff = filefinder.FileFinder("", "{num}", test_paths=["1", "2"])
ff.find_files(num=1)

the workaround is:

ff.find_files(num=[1])

[mathause]

I do wonder why this works for strings - it should not iterate the individual letters?

[mathause]

They are wrapped in:

https://github.com/mathause/filefinder/blob/ab49e18fe0563dcb526cdc62d1ee05342cc67b7b/filefinder/_filefinder.py#L86-L89

[mathause]

Maybe:

if isinstance(value, str) or np.ndim(value) == 0:
    ...