CB-9782 Implements PlatformApi contract for Android platform.

This closes #226

node_modules/shelljs/src/cd.js

@@ -0,0 +1,19 @@
+var fs = require('fs');
+var common = require('./common');
+
+//@
+//@ ### cd('dir')
+//@ Changes to directory `dir` for the duration of the script
+function _cd(options, dir) {
+  if (!dir)
+    common.error('directory not specified');
+
+  if (!fs.existsSync(dir))
+    common.error('no such file or directory: ' + dir);
+
+  if (!fs.statSync(dir).isDirectory())
+    common.error('not a directory: ' + dir);
+
+  process.chdir(dir);
+}
+module.exports = _cd;