Saltext.proxmox

Fixed

- Fixed profile error: name '__opts__' is not defined [45](https://github.com/salt-extensions/saltext-proxmox/issues/45)

Changed

- changed parameter structure for profiles [9](https://github.com/salt-extensions/saltext-proxmox/issues/9)
- removed custom parameters for VMs (ip_address). instead, VM parameters are forwarded directly to proxmox api [21](https://github.com/salt-extensions/saltext-proxmox/issues/21)
- removed arbitrary limit for indexed parameters. instead, VM parameters are forwarded directly to proxmox api [29](https://github.com/salt-extensions/saltext-proxmox/issues/29)


Added

- VM parameters are forwarded directly to proxmox api. the documentation references the proxmox api docs to look up possible parameters [12](https://github.com/salt-extensions/saltext-proxmox/issues/12)

Removed

- removed superfluous code from `_get_properties()` and its callees (8)
- removed dead code from repository (20)
- removed OpenVZ code paths (27)

Changed

- Replaced IPy dependency with built-in module ipaddress (22)

Fixed

- fixed location parameter for `avail_images()` (25)

Added

- Initial version of Proxmox Cloud Modules Extension for Salt. This release
tracks the functionality in the core Salt code base as of version 3006.0.