Added CreateVolume to EC2 API
Merge pull request #278 from libc/add-create-volume-to-ec2

Added CreateVolume to EC2 API
Standardise error handling

- 400 errors would pass through some functions
- Extraneous panic() on error
Merge pull request #279 from sweeney/kinesis_error_handling

Standardise Kinesis error handling
Add condition expression support

Reimplement older mechanisms on expressions

Update query builder tests