Add AWS Cost Explorer forecast functionality#1160

NithinChandranR-AWS wants to merge 2 commits intoaws-solutions-library-samples:mainaws-solutions-library-samples/cloud-intelligence-dashboards-framework:mainfrom

NithinChandranR-AWS:add-cost-forecastNithinChandranR-AWS/aws-cudos-framework-deployment:add-cost-forecastCopy head branch name to clipboard