* Removed Tags field from create_subnet response.
* Added DefaultForAz to create_subnet response.
* Added MapPublicIpOnLaunch to create_subnet response.
* Added OwnerId to create_subnet response.
* Added AssignIpv6AddressOnCreation field for create_subnet and describe_subnet and implemented setting it in modify_subnet_attribute.
* Added SubnetArn to create_subnet response.
* Added AvailabilityZoneId to create_subnet and describe_subnet responses, and error for invalid availability zone.
* Added Ipv6CidrBlockAssociationSet to create_subnet response.
* Added missing fields to describe_subnets response.
* Added myself to list of contributors and marked describe_subnet as implemented.
* Fixed linting errors.
* Fixed blank line containing a tab.
* Fixed accidentally deleted ).
* Fixed broken tests.
* Fixed a bug where default network ACL entries could not be deleted.
* Implemented throwing error when a network entry with the same rule number and egress value already exists.
* Fixed syntax errors.
* Added socket.timeout to possibly raised exceptions in wait_for for Python 3.