Add new option "gcp_init" for acloud setup

- Setup user information in gcloud config file
- Enable gcloud API service
- Generate SSH key

Bug: 110856450
Test: ./run_tests.sh, m acloud && acloud setup --gcp_init
acloud setup
Change-Id: I88d6e52cb5164e023023bf9c5c62b93c87c8bc3f
9 files changed