upgrade CI to use travis' `Trusty` environment from the previous `Precise`. Per Travis CI documentation (https://docs.travis-ci.com/user/ci-environment/#Virtualization-environments) this should get us VMs provisioned with 7.5G memory
upgrade CI to use travis' `Trusty` environment from the previous `Precise`. Per Travis CI documentation (https://docs.travis-ci.com/user/ci-environment/#Virtualization-environments) this should get us VMs provisioned with 7.5G memory

amarzavery/azure-xplat-cli,amarzavery/azure-xplat-cli,Azure/azure-xplat-cli,huangpf/azure-xplat-cli,Azure/azure-xplat-cli,huangpf/azure-xplat-cli,amarzavery/azure-xplat-cli,yugangw-msft/azure-sdk-tools-xplat,yugangw-msft/azure-xplat-cli,yugangw-msft/azure-sdk-tools-xplat,yugangw-msft/azure-sdk-tools-xplat,yugangw-msft/azure-xplat-cli,huangpf/azure-xplat-cli,yugangw-msft/azure-xplat-cli,Azure/azure-xplat-cli,yugangw-msft/azure-xplat-cli,yugangw-msft/azure-xplat-cli,amarzavery/azure-xplat-cli,Azure/azure-xplat-cli,amarzavery/azure-xplat-cli,Azure/azure-xplat-cli