Add Pattern.parameters to get cfn-template parameters
Add Link header to response headers when list resources
List/Show application returns only specified system's application
Change response format from Array to Hash on GET /patterns/:id/parameters
Fix some error response
Merge branch 'feature/fix_api_for_cli' into develop
Change name to candidate from available_cloud
Add stack model
Refactoring: add cloud on stack and remove unnecessary specs
Add protocol column on patterns table
Implement Stack#payload to create payload when configure
Split status of stack to :PENDING, :READY, :PROGRESS, :CREATE_COMPLETE and :ERROR
Add template_parameters column on System
Add Stack.created scope to retrieve created stacks
Rebuild stack observer that use system and stacks to accept optional pattern
Refactoring: add a bit spec on System#template_parameters
Change command for create patterns by packer to support optional pattern
Add StacksController
Mount StackController on /stacks
Return symbolized type on pattern