<!--- 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
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


devices[device] = k
    results['mac'] = mac
    results['devices'] = devices
    results['vmid'] = int(vmid)
def settings(module, proxmox, vmid, node, name, timeout, **kwargs):
    proxmox_node = proxmox.nodes(node)
    # 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)
    if getattr(proxmox_node, VZ_TYPE)(vmid).config.set(**kwargs) is None:
        return True
    else:
        return False
def create_vm(module, proxmox, vmid, newid, node, name, memory, cpu, cores, sockets, timeout, update, **kwargs):
    # Available only in PVE 4
    only_v', 'skiplock']
    # valide clone parameters
    valid_ 'full', 'pool', 'snapname', 'storage', 'target']
    clone_params = {}
    # Default args for vm. Note: -args option is for experts only. It allows you to pass arbitrary arguments to kvm.
    vm_args = "-serial unix:/var/run/qemu-server/{0}.serial,server,nowait".format(vmid)
    proxmox_node = proxmox.nodes(node)
    # 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)
    kwargs.update(dict([k, int(v)] for k, v in kwargs.items() if isinstance(v, bool)))
    # The features work only on PVE 4
    
        for p in only_v4:
            if p in kwargs:
                del kwargs[p]
    # If update, don't update disk (virtio, ide, sata, scsi) and network interface