use list_flavors from knife-cloud.
move ebs and vpc options to separate methods to make before_exec simpler.
move eip setup code to #associate_eip
eip validation should raise proper exception.
validate tags and cache hashed_tags extraction.
refactor server summary info.
Added changes to resolved short option ambiguity
Added changes to set hint config before bootstrap
Added rspec test for hint config change
Merge pull request #193 from ClogenyTechnologies/sid-oc-11210-short-opt-ambiguity

OC-11210 EC2 refactored code has ambiguity in the name of short-option for Gateway & Groups
Added changes to catch/handle fog errors in knife-ec2
Added rspec tests for fog error handling
Implemented review comments to rename list_flavors to list_resource_configurations
Merge pull request #191 from ClogenyTechnologies/kd/OC-11204-abstractions

OC-11204 - Exception handling and abstraction
Incorporated review comments to display fog error message
Merge pull request #194 from ClogenyTechnologies/sid-oc-11207-ec2-vpc-cloudmetadata

OC-11207 Chef Node doesn't have Ec2 Cloud metadata in its attributes when it created and bootstrap in VPC
Handled review comments to parse fog error messages
Added changes to catch/handle fog errors in knife-ec2
Added rspec tests for fog error handling
Incorporated review comments to display fog error message