Correct typos

Rename module to be consistent with the real name of the GCP service
Add link to the module on READMEs

modules/endpoints/variables.tf

@@ -0,0 +1,53 @@
+/**
+ * Copyright 2020 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+variable "grpc_config" {
+  description = "The configuration for a gRPC enpoint. Either this, openapi_config must be specified."
+  type        = object({
+    yaml_path          = string
+    protoc_output_path = string
+  })
+}
+
+variable "iam_roles" {
+  description = "Authoritative for a given role. Updates the IAM policy to grant a role to a list of members."
+  type        = list(string)
+  default     = []
+}
+
+variable "iam_members" {
+  description = "Authoritative for a given role. Updates the IAM policy to grant a role to a list of members. Other roles within the IAM policy for the instance are preserved."
+  type        = map(list(string))
+  default     = {}
+}
+
+variable "openapi_config" {
+  description = "The configuration for an OpenAPI endopoint. Either this, grpc_config must be specified."
+  type        = object({
+    yaml_path = string
+  })
+}
+
+variable "project_id" {
+  description = "The project ID that the service belongs to."
+  type        = string
+  default     = null
+}
+
+variable "service_name" {
+  description = "The name of the service. Usually of the form '$apiname.endpoints.$projectid.cloud.goog'."
+  type        = string
+}