add env-template for aws. .env file in the root of the project to be consumed by dotenv.

commit 18eadf69 
Author: Yunhua Koglin <kogliny@amazon.com> 
Date: Fri Jan 08 2021 11:00:38 GMT-0600 (Central Standard Time) 

    add env sample for aws

docs/templates/.env-sample-aws

+#cloud provider is set to aws 
+CLOUDPROVIDER= "aws"
+
+#specify service port, default is 5000
+PORT= 5000
+
+API_BASE_PATH=/api/v3
+SERVICE_ENV=
+IMP_SERVICE_ACCOUNT_SIGNER=
+AWS_REGION=
+
+# redis instance url (defautl port 6379)
+LOCKSMAP_REDIS_INSTANCE_ADDRESS=
+LOCKSMAP_REDIS_INSTANCE_PORT= 6379
+LOCKSMAP_REDIS_INSTANCE_KEY=
+
+DES_REDIS_INSTANCE_ADDRESS=
+DES_REDIS_INSTANCE_PORT=
+DES_REDIS_INSTANCE_KEY=
+DES_SERVICE_HOST=
+DES_SERVICE_APPKEY=
+
+JWKS_URL=
+JWT_EXCLUDE_PATHS=
+JWT_AUDIENCE=
+
+
+# Features to disable ONLY the service run locally
+JWT_ENABLE_FEATURE= "false"
+FEATURE_FLAG_AUTHORIZATION= "false"
+FEATURE_FLAG_LEGALTAG= "false"
+FEATURE_FLAG_SEISMICMETA_STORAGE= "false"
+FEATURE_FLAG_IMPTOKEN= "false"
+FEATURE_FLAG_STORAGE_CREDENTIALS= "false"
+FEATURE_FLAG_TRACE= "false"
+FEATURE_FLAG_LOGGING= "false"
+FEATURE_FLAG_STACKDRIVER_EXPORTER= "false"