Add Terraform to Workspace

Added Terraform (www.terraform.io) binary to workspace container.
This tool is useful to spawn resources to multiple cloud providers via config files.

docker-compose.yml

@@ -38,6 +38,7 @@ services:
           - INSTALL_PYTHON=${WORKSPACE_INSTALL_PYTHON}
           - INSTALL_IMAGE_OPTIMIZERS=${WORKSPACE_INSTALL_IMAGE_OPTIMIZERS}
           - INSTALL_IMAGEMAGICK=${WORKSPACE_INSTALL_IMAGEMAGICK}
+          - INSTALL_TERRAFORM=${WORKSPACE_INSTALL_TERRAFORM}
           - PUID=${WORKSPACE_PUID}
           - PGID=${WORKSPACE_PGID}
           - NODE_VERSION=${WORKSPACE_NODE_VERSION}