JENKINS-20789: manage new instances (C3, G2, HI, HS, CC2, CR1)

Upgraded to com.amazonaws:aws-java-sdk:1.6.7
Added support for C3Large, C3Xlarge, G22xlarge, C32xlarge, Hi14xlarge, Hs18xlarge, C34xlarge, Cc28xlarge, Cr18xlarge, C38xlarge EC2 instance types.