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<!--- Also test if the latest release and devel branch are affected too -->
<!--- Complete *all* sections as described, this form is processed automatically -->

##### SUMMARY
<!--- Explain the problem briefly below -->
We publish semver collection (vyos.vyos:0.0.1-dev58) to ansible galaxy, however by default it seems ansible-galaxy client will not be able to find it. You must specific the version number directly to fetch it.

https://galaxy.ansible.com/vyos/vyos


EDIT:

This is working as expect, but it would be nice to Include:

   --pre                       Include pre-release and development versions. By default, ansible-galaxy only finds stable versions.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
<!--- Write the short name of the module, plugin, task or feature below, use your best guess if unsure -->
ansible-galaxy

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```paste below
ansible 2.9.1
```

##### CONFIGURATION
<!--- Paste verbatim output from "ansible-config dump --only-changed" between quotes -->
```paste below

```


##### STEPS TO REPRODUCE
<!--- Describe exactly how to reproduce the problem, using a minimal test-case -->

<!--- Paste example playbooks or commands between quotes below -->
```yaml
$ ansible-galaxy collection install vyos.vyos -p /tmp/11123
[WARNING]: The specified collections path '/tmp/11123' is not part of the configured Ansible collections paths '/home/pabelanger/.ansible/collections:/usr/share/ansible/collections'. The
installed collection won't be picked up in an Ansible run.

Process install dependency map
ERROR! Cannot meet requirement * for dependency vyos.vyos from source 'https://galaxy.ansible.com/api/'. Available versions before last requirement added: 
Requirements from:
	base - 'vyos.vyos:*'
(venv) [pabelanger@localhost openstack]$ ansible-galaxy collection install vyos.vyos:0.0.1-dev57 -p /tmp/11123
[WARNING]: The specified collections path '/tmp/11123' is not part of the configured Ansible collections paths '/home/pabelanger/.ansible/collections:/usr/share/ansible/collections'. The
installed collection won't be picked up in an Ansible run.

Process install dependency map
Starting collection install process
Installing 'vyos.vyos:0.0.1-dev57' to '/tmp/11123/ansible_collections/vyos/vyos'
```

<!--- HINT: You can paste gist.github.com links for larger files -->

##### EXPECTED RESULTS
<!--- Describe what you expected to happen when running the steps above -->
vyos.vyos collection to be found and installed

##### ACTUAL RESULTS
<!--- Describe what actually happened. If possible run with extra verbosity (-vvvv) -->

<!--- Paste verbatim command output between quotes -->
```paste below

```

roles_left.append(dep_role)
                                else:
                                    display.warning('- dependency %s (%s) from role %s differs from already installed version (%s), skipping' %
                                                    (to_text(dep_role), dep_role.version, role.name, dep_role.install_info['version']))
                            else:
                                if force_deps:
                                    roles_left.append(dep_role)
                                else:
                                    display.display('- dependency %s is already installed, skipping.' % dep_role.name)
            if not installed:
                display.warning("- %s was NOT installed successfully." % role.name)
                self.exit_without_ignore()
        return 0
    def execute_remove(self):
        """
        removes the list of roles passed as arguments from the local system.
        """
        if not context.CLIARGS['args']:
            raise AnsibleOptionsError('- you must specify at least one role to remove.')
        for role_name in context.CLIARGS['args']:
            role = GalaxyRole(self.galaxy, self.api, role_name)
            try:
                if role.remove():
                    display.display('- successfully removed %s' % role_name)
                else:
                    display.display('- %s is not installed, skipping.' % role_name)
            except Exception as e:
                raise AnsibleError("Failed to remove role %s: %s" % (role_name, to_native(e)))
        return 0
    def execute_list(self):