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##### SUMMARY
<!--- Explain the problem briefly below, add suggestions to wording or structure -->
In the user module, in the docs for the password field, there is a link to instructions on how to create a password hash for the module to consume. Said link is broken, and gives a 404.


Cf. [the corresponding line in the user module](https://github.com/ansible/ansible/blob/2b0cd2c13f2021f839600d601f75dea2c0343ed1/lib/ansible/modules/user.py#L92)


> HINT: Did you know the documentation has an "Edit on GitHub" link on every page ?

this one doesn't, or i just could not find it : /

##### ISSUE TYPE
- Documentation Report

##### COMPONENT NAME
<!--- Write the short name of the rst file, module, plugin, task or feature below, use your best guess if unsure -->
user module
##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
latest
```

'''Convert SELF.GROUP to is stringed numerical value suitable for dscl.'''
        if self.group is None:
            self.group = 'nogroup'
        try:
            self.group = grp.getgrnam(self.group).gr_gid
        except KeyError:
            self.module.fail_json(msg='Group "%s" not found. Try to create it first using "group" module.' % self.group)
        
        self.group = str(self.group)
    def __modify_group(self, group, action):
        '''Add or remove SELF.NAME to or from GROUP depending on ACTION.
        ACTION can be 'add' or 'remove' otherwise 'remove' is assumed. '''
        if action == 'add':
            option = '-a'
        else:
            option = '-d'
        cmd = ['dseditgroup', '-o', 'edit', option, self.name, '-t', 'user', group]
        (rc, out, err) = self.execute_command(cmd)
        if rc != 0:
            self.module.fail_json(msg='Cannot %s user "%s" to group "%s".'
                                      % (action, self.name, group), err=err, out=out, rc=rc)
        return (rc, out, err)
    def _modify_group(self):