If you have a conflict with the previous version:
- Select Help > Install New Software
- Click on already installed
- Select all Android software on version 22.*
- Click on Uninstall
- Work with: https://dl-ssl.google.com/android/eclipse/
- Select Developer Tools and Next
- Next, Accept the license agreement and Finish.
EDIT :
This trick is probably no more necessary!
Try to upgrade your SDK tools to 23.0.2+ and build&platform tools to rev 20 before.