Update schema and docs to describe name as optional

Fixes: #316

docs/schema.md

@@ -51,10 +51,12 @@ services:
 
 ### Root Properties
 
-#### `name` (string) *required*
+#### `name` (string)
 
 Configures the name of the application. This will appear in some Kubernetes labels right now, but not many other places.
 
+If the name name is not specified, then the lowercased directory name containing the `tye.yaml` file will be used as the default.
+
 #### `registry` (string)
 
 Allows storing the name of the container registry in configuration. This is used when building and deploying images for two purposes:

src/schema/tye-schema.json

@@ -37,7 +37,6 @@
         }
     },
     "required": [
-        "name",
         "services"
     ],
     "definitions": {