New USB-C charger to be used on an old MagSafe2 Macbook Pro Are there any adaptors so I can use the new MacBook Pro USB-C Charger in my old Magsafe 2 MacBook Pro? 

I know one day I am going to buy the new MacBook Pro and my old original charger broke on a trip, so I want to buy the new one as I use two chargers, one lives in my traveling bag and the other stays home.
There is no adapter that goes from USB-C to Magsafe 2.  Though there is a project to create turn a USB-C into a MagSafe adapter

Tech accessories usually don't go backwards and it's usually because the old accessories don't have the capability to communicate properly with the new devices (i.e. voltage negotiation with USB-C charging).

Unfortunately, you will have to get an older charger to support that MacBook Pro.