Version 1.6.0

[zolstein]

Adds support for Pure Storage FlashArray REST versions 1.5 and 1.6

New features:

• Verify SSL certificates for HTTPS requests
• Set HTTP User-Agent for requests

New APIs:

• create_subnet(self, subnet, prefix, **kwargs): Create a subnet. Requires use of REST API 1.5 or later.
• delete_subnet(self, subnet): Delete a subnet. Requires use of REST API 1.5 or later.
• disable_subnet(self, subnet): Disable a subnet. Requires use of REST API 1.5 or later.
• enable_subnet(self, subnet): Enable a subnet. Requires use of REST API 1.5 or later.
• get_subnet(self, subnet): Return a dictionary describing a subnet. Requires use of REST API 1.5 or later.
• list_subnets(self, **kwargs): Return list of dictionaries describing each subnet. Requires use of REST API 1.5 or later.
• rename_subnet(self, subnet, name): Rename a subnet. Requires use of REST API 1.5 or later.
• set_subnet(self, subnet, **kwargs): Set subnet attributes. Requires use of REST API 1.5 or later.
• create_vlan_interface(self, interface, subnet, **kwargs): Create a vlan interface. Requires use of REST API 1.5 or later.
• delete_vlan_interface(self, interface): Delete a vlan interface. Requires use of REST API 1.5 or later.
• throttle_array_connections(self, address, **kwargs): Set bandwidth limits on a connection. Requires use of REST API 1.5 or later.

Other:

- Fixes a bug where attributes of purestorage module could only be
  referenced using purestorage.purestorage explicitly in Python 3.