fix: check for old version of the CLI on empty project

Fix #2135
Close #2178

Author: ValeryVS

Diff for: packages/angular-cli/upgrade/version.ts

@@ -76,6 +76,11 @@ export class Version {
 
 
     const configPath = CliConfig.configFilePath();
+
+    if (configPath === null) {
+      return new Version(null);
+    }
+
     const configJson = readFileSync(configPath, 'utf8');
 
     try {

Diff for: tests/e2e/tests/misc/version.ts

@@ -0,0 +1,10 @@
+import {deleteFile} from '../../utils/fs';
+import {ng} from '../../utils/process';
+
+
+export default function() {
+  return ng('version')
+    .then(() => deleteFile('angular-cli.json'))
+    // doesn't fail on a project with missing angular-cli.json
+    .then(() => ng('version'));
+}