build: add GraphQL autocompletion and validation

Author: felixfbecker

apollo.config.js

@@ -0,0 +1,10 @@
+// For autocompletion in .graphql files in VS Code.
+module.exports = {
+  client: {
+    service: {
+      name: 'sourcegraph',
+      url: 'https://sourcegraph.com/.api/graphql',
+    },
+    includes: ['./PSSourcegraph/queries/**/*.graphql'],
+  },
+}