Add a "lastest available release" information

Created by: galuel

Sakia should give the user information the latest available version on the software (it is yet done), and also on its official site sakia-wallet.org.

It is possible to do it in javascript like here : http://geconomicus.glibre.org/latestreleases.html

So people with version 1.7 will be aware it exists a version 1.9 for instance, and so he can update knowing the information.

To upload designs, you'll need to enable LFS and have an admin enable hashed storage. More information