codespell 1.5
Install binary file as 'codespell' instead of 'codespell.py'

Users don't have to know that this tool is written in Python
Move dictionary name to optional parameters

Most often users need default dictionary, so let's create an option
with default value set to dictonary.txt. Users can overwrite this
parameter with its own dictionary.
Use current directory if '-r' specified and no input files

If '-r' recursive flag is specified there is no reason to use
stdin. Recursive is applied to directories only.