Wrote unit test for commands.pullFolder
Wrote unit test for commands.pullFolder

* Wrote a test that mocks 'driver.adb.pull' so that I could test pullFolder with local files
* Tests that it can zip a local folder to a base64 zip
* Writes base64 zip to a zip file, unzips it and confirms it has the same contents as the original local folder

vmaxim/appium-android-driver