Updates to support new LaunchConfiguration properties and create options

Support new LaunchConfigurationCreateOptions from
TheWeatherCompany/dasein-cloud-core#49
Add support for creating and getting LaunchConfigurations with:
AssociatePublicIpAddress, EbsOptimized, InstanceId, and
BlockDeviceMapping.

Also fixed some whitespace inconsistency.

Ref #69
Update VolumeAttachment class changes

Ref #69