add staging support

Can you make a staging option? I often test maps on staging and love to Rust Sever Tool for my rust main servers but often of times using the Rust FP undocumented away of running staging can make things all wonky if you dont do it right. I love how simple your solution is for local hosting of Rust main branch hosting and would like to see the simplicity of rust staging branch hosting. 

just seen your other solution : 

up to you to add it or not to this solution  

I can do that as soon as I have more time again, unfortunately it won't be possible in the next few days.

Changed Status from Pending to Closed

Changed Fixed In to Next Version