Allow specifying EC2 instance types besides t1.micro
Update boto library version
Full support for AWS regions outside us-east-1

- Sets up boto connection with the appropriate region (auto-detected from user-specified zone)
- Instances running in these regions can be queried successfully with "report" command
- Fixes launching of private AMIs outside default us-east-1 region
Merge pull request #40 from nfarina/custom_instance_types

Allow specifying EC2 instance types besides t1.micro
Merge pull request #41 from nfarina/full_zone_support

Full support for all AWS Availability Zones