This commit modifies the response format of the ec2 calls
`create_volume` and `describe_volumes`. Previously, these calls would
always include a `Tags` key in the response, even when a volume has no tags.
Now, the `Tags` key will not be included in the response if the volume
has no tags.
When an EBS volume has no tags, calls to the aws ec2 endpoints `create_volume`
and `describe_volumes` do not include the `Tags` key in the
`response.Volumes[]` object.
However, moto does include the `Tags` key in this case. This discrepancy
in behaviour can result in code passing a moto test but failing in
production.
Sample snippets that trigger this condition:
```
def create_volume_and_then_get_tags_from_response():
client = boto3.client('ec2', region_name='us-east-1')
volume_response = client.create_volume(
Size=10,
AvailabilityZone='us-east-1a'
)
keys = volume_response['Keys']
```
```
def create_volume_and_then_get_tags_from_describe_volumes():
client = boto3.client('ec2', region_name='us-east-1')
volume_response = client.create_volume(
Size=10,
AvailabilityZone='us-east-1a'
)
volume_describe_response = client.describe_volumes()
keys = volume_describe_response['Volumes'][0]['Keys']
```
Both sample snippets will succeed in a moto test, but fail with a
`KeyError` when using the aws api.
* Delete the volume used during AMI creation
Creating an AMI doesn't actually result in the creation of an EBS
volume, although the associated snapshot does reference one. To that
end, delete the volume once we've used it.
* Add `owner_id` to `Snapshot`, verify AMI snapshots
The default AMIs which are created by moto have EBS volume mappings
but the snapshots associated with those don't have the correct
owners set.
This adds the owner to the snapshot model and passes it through from
the JSON data.
The AWS docs say that: "Currently, the resource types that support
tagging on creation are instance and volume." Calling `create_volume`
and passing `image` as the resource type in tag specifications causes
an `InvalidParameterValue` error.
Volumes and Snapshots to be searchable by their id
Placement of instance to match region connection
Times for creation and attachment to show based on api call
