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##### SUMMARY
`ansible-galaxy collection install ...` will create a file to save the galaxy token in `~/.ansible_galaxy`. This causes problems when the users home dir isn't writeable and potential problems in a multi-tenant shared-user environment.

##### ISSUE TYPE
- Feature Idea

##### COMPONENT NAME
ansible-galaxy collection

##### ADDITIONAL INFORMATION
I would like a knob to be able to tell `ansible-galaxy` not to create that file or a knob to specify the directory where the file can be created. Below is the traceback I get when my home dir doesn't allow write access.

##### Steps to recreate
`HOME=/ ansible-galaxy -vvv collection install chrismeyersfsu.tower_modules -p /tmp/here`

``` 
ansible-galaxy 2.9.0.dev0
  config file = /etc/ansible/ansible.cfg
  configured module search path = [u'/.ansible/plugins/modules', u'/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python2.7/site-packages/ansible
  executable location = /usr/bin/ansible-galaxy
  python version = 2.7.5 (default, Jun 20 2019, 20:27:34) [GCC 4.8.5 20150623 (Red Hat 4.8.5-36)]
Using /etc/ansible/ansible.cfg as config file
ERROR! Unexpected Exception, this is probably a bug: [Errno 13] Permission denied: '//.ansible_galaxy'
the full traceback was:

Traceback (most recent call last):
  File "/usr/bin/ansible-galaxy", line 111, in <module>
    exit_code = cli.run()
  File "/usr/lib/python2.7/site-packages/ansible/cli/galaxy.py", line 267, in run
    self.api = GalaxyAPI(self.galaxy)
  File "/usr/lib/python2.7/site-packages/ansible/galaxy/api.py", line 65, in __init__
    self.token = GalaxyToken()
  File "/usr/lib/python2.7/site-packages/ansible/galaxy/token.py", line 39, in __init__
    self.config = yaml.safe_load(self.__open_config_for_read())
  File "/usr/lib/python2.7/site-packages/ansible/galaxy/token.py", line 48, in __open_config_for_read
    f = open(self.file, 'w')
IOError: [Errno 13] Permission denied: '//.ansible_galaxy'
```

"""
        Retrieve an authentication token
        """
        url = '%s/tokens/' % self.baseurl
        args = urlencode({"github_token": github_token})
        resp = open_url(url, data=args, validate_certs=self._validate_certs, method="POST")
        data = json.loads(to_text(resp.read(), errors='surrogate_or_strict'))
        return data
    @g_connect
    def create_import_task(self, github_user, github_repo, reference=None, role_name=None):
        """
        Post an import request
        """
        url = '%s/imports/' % self.baseurl
        args = {
            "github_user": github_user,
            "github_repo": github_repo,
            "github_reference": reference if reference else ""
        }
        if role_name:
            args['alternate_role_name'] = role_name
        elif github_repo.startswith('ansible-role'):
            args['alternate_role_name'] = github_repo[len('ansible-role') + 1:]
        data = self.__call_galaxy(url, args=urlencode(args), method="POST")
        if data.get('results', None):
            return data['results']
        return data
    @g_connect
    def get_import_task(self, task_id=None, github_user=None, github_repo=None):