<!--- Verify first that your issue is not already reported on GitHub -->
<!--- 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

```

elif not force:
                raise AnsibleError("- the directory %s already exists. "
                                   "You can use --force to re-initialize this directory,\n"
                                   "however it will reset any main.yml files that may have\n"
                                   "been modified there already." % to_native(obj_path))
        if obj_skeleton is not None:
            own_skeleton = False
            skeleton_ignore_expressions = C.GALAXY_ROLE_SKELETON_IGNORE
        else:
            own_skeleton = True
            obj_skeleton = self.galaxy.default_role_skeleton_path
            skeleton_ignore_expressions = ['^.*/.git_keep$']
        obj_skeleton = os.path.expanduser(obj_skeleton)
        skeleton_ignore_re = [re.compile(x) for x in skeleton_ignore_expressions]
        if not os.path.exists(obj_skeleton):
            raise AnsibleError("- the skeleton path '{0}' does not exist, cannot init {1}".format(
                to_native(obj_skeleton), galaxy_type)
            )
        template_env = Environment(loader=FileSystemLoader(obj_skeleton))
        
        if not os.path.exists(b_obj_path):
            os.makedirs(b_obj_path)
        for root, dirs, files in os.walk(obj_skeleton, topdown=True):
            rel_root = os.path.relpath(root, obj_skeleton)
            rel_dirs = rel_root.split(os.sep)
            rel_root_dir = rel_dirs[0]
            if galaxy_type == 'collection':
                
                in_templates_dir = rel_root_dir in ['playbooks', 'roles'] and 'templates' in rel_dirs
            else: