[Feature request]: Better scripting support

Hello there 

I would like to be able to script what repository i have open / in focus.
Preferably it could just be via the binary with a command line argument, e.g.:

`/Applications/SourceGit.app/Contents/MacOS/SourceGit <SOME_REPO>`

My goal is to try and track what project i have open in my IDE and make SourceGit reflect that on a separate monitor.

Thanks in advance.