Invalid version ^0.9.13

Hello, 

I wanted to play with regex to enhance our issue tracking support and your apps could definitely help me with this.

I tried to load the package in our rocketchat instance (in Admin) but I had the error "Invalid version ^0.9.13".

I see in your app.json that it's the requiredApiVersion number, but I don't understand why it's not valid. 

Thank you for your help.
