Add version warning when user has Vagrant < 1.8
Add version warning when user has Vagrant < 1.8

KaGeN101/mantl,mantl/mantl,abn/microservices-infrastructure,abn/microservices-infrastructure,phnmnl/mantl,sehqlr/mantl,sehqlr/mantl,datascienceinc/mantl,CiscoCloud/microservices-infrastructure,ContainerSolutions/microservices-infrastructure,CiscoCloud/microservices-infrastructure,ContainerSolutions/microservices-infrastructure,bitium/mantl,phnmnl/mantl,CiscoCloud/mantl,abn/microservices-infrastructure,KaGeN101/mantl,bitium/mantl,mantl/mantl,CiscoCloud/mantl,datascienceinc/mantl