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##### SUMMARY
When I read the `copy` documentation, I couldn't work out what it meant.  Unfortunately, this meant it sounded like it might be a weird sex joke.

It doesn't sound like a big problem, but in an ideal world, I think we should prefer to avoid weird sex jokes in an alias for a parameter called `force`.

##### ISSUE TYPE
- Feature Idea

##### COMPONENT NAME
copy

##### ADDITIONAL INFORMATION
Issue search tells me "thirsty" was added as an option to the `get_url` module.  In that context, it is appropriate.  But in the context of the `copy` module, it does not make sense, because `copy` only works in the upload direction.

The first three pages of Google Search results (Ansible thirsty) show people using "thirsty" for downloads only, not uploads.  Similarly for GitHub code search (copy thirsty language:YAML).
''' Return MD5 hex digest of local file using digest_from_file().
        Do not use this function unless you have no other choice for:
            1) Optional backwards compatibility
            2) Compatibility with a third party protocol
        This function will not work on systems complying with FIPS-140-2.
        Most uses of this function can use the module.sha1 function instead.
        '''
        if 'md5' not in AVAILABLE_HASH_ALGORITHMS:
            raise ValueError('MD5 not available.  Possibly running in FIPS mode')
        return self.digest_from_file(filename, 'md5')
    def sha1(self, filename):