Merge branch 'terraform-1.0' into 'master'

support Terraform 1.0

Closes #3

See merge request !3

versions.tf

@@ -6,5 +6,5 @@ terraform {
     google-beta = "~> 3.63"
   }
 
-  required_version = "~> 0.13"
+  required_version = "> 0.13, < 2.0.0"
 }