Sort Validation warning and errors

Make the UI output consistent

terraform/context.go

@@ -665,6 +665,12 @@ func (c *Context) Validate() ([]string, []error) {
 
 	// Return the result
 	rerrs := multierror.Append(errs, walker.ValidationErrors...)
+
+	sort.Strings(walker.ValidationWarnings)
+	sort.Slice(rerrs.Errors, func(i, j int) bool {
+		return rerrs.Errors[i].Error() < rerrs.Errors[j].Error()
+	})
+
 	return walker.ValidationWarnings, rerrs.Errors
 }