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##### SUMMARY
An hour ago I upgraded my Proxmox to the new stable version 6. Since then my playbooks fail with this error:
`fatal: [proxmox]: FAILED! => {"changed": false, "msg": "authorization on proxmox cluster failed with exception: could not convert string to float: '6.0-4'"}`

It seems like the proxmox changed the API.

##### ISSUE TYPE
- Bug Report

##### COMPONENT NAME
proxmox (https://github.com/mrdrogdrog/ansible/blob/6430205d396b7c1733de22a898c51823f67d5bf4/lib/ansible/modules/cloud/misc/proxmox.py#L484)

##### ANSIBLE VERSION
<!--- Paste verbatim output from "ansible --version" between quotes -->
```
ansible 2.8.2
  config file = /etc/ansible/ansible.cfg
  configured module search path = ['/home/tilman/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /usr/lib/python3.7/site-packages/ansible
  executable location = /usr/bin/ansible
  python version = 3.7.3 (default, Jun 24 2019, 04:54:02) [GCC 9.1.0]
```


##### OS / ENVIRONMENT
Proxmox 6 


##### STEPS TO REPRODUCE
- Use the latest ansible version
- Use the latest stable version of proxmox (6)
- Use the proxmox module to do anything. E.g. create a container
- Get the error


##### EXPECTED RESULTS
Normal runthrough

##### ACTUAL RESULTS
Crash with an error


global results
    results = {}
    mac = {}
    devices = {}
    try:
        vm = proxmox.nodes(node).qemu(vmid).config.get()
    except Exception as e:
        module.fail_json(msg='Getting information for VM with vmid = %s failed with exception: %s' % (vmid, e))
    # Sanitize kwargs. Remove not defined args and ensure True and False converted to int.
    kwargs = dict((k, v) for k, v in kwargs.items() if v is not None)
    # Convert all dict in kwargs to elements. For hostpci[n], ide[n], net[n], numa[n], parallel[n], sata[n], scsi[n], serial[n], virtio[n]
    for k in list(kwargs.keys()):
        if isinstance(kwargs[k], dict):
            kwargs.update(kwargs[k])
            del kwargs[k]
    # Split information by type
    for 
        if re.match(r'net[0-9]', k) is not None:
            interface = k
            k = vm[k]
            k = re.search('=(.*?),', k).group(1)
            mac[interface] = k
        if (re.match(r'virtio[0-9]', k) is not None or
                re.match(r'ide[0-9]', k) is not None or
                re.match(r'scsi[0-9]', k) is not None or
                re.match(r'sata[0-9]', k) is not None):
            device = k
            k = vm[k]
            k = re.search('(.*?),', k).group(1)