ci: Add .circleci/config.yml (#687)
ci: Add .circleci/config.yml (#687)

We'll let it run for a couple PRs then remove Travis completely.
WIth this, we could also remove `scripts/install.sh` and `scripts/cleanup.sh`.
angular/vscode-ng-language-service,angular/vscode-ng-language-service,angular/vscode-ng-language-service,angular/vscode-ng-language-service