Adding check to doctor/dev.js for checking ant,adb,android-16 and android-18 #2752

style changes to doctor/dev.js

Adding check to doctor/dev.js for checking ant,adb,android-16 and android-18 #2752
Added TestApp.zip asset
better app url handling
Fixed the url for appium-adb submodule.

Removing extra spaces
Fixing confilcts