Pass value for 'shell' as argument.

• I am on the latest Hyper.app version
• I have searched the issues of this repo and believe that this is not a duplicate

• OS version and name: Windows 10.0.15063-64 Bit
• Hyper.app version: 1.3.2
• Link of a Gist with the contents of your .hyper.js: https://gist.github.com/matracey/130d1fe10d7bb9542ea60bc7e09c4dd8
• Relevant information from devtools: N/A
• The issue is reproducible in vanilla Hyper.app: Is Vanilla.

Issue

Just discovered and installed hyper and it's exactly what I was looking for from a terminal, except for one thing. I'm looking to create multiple shortcuts to Hyper, each one for a different terminal (Bash, CMD, PowerShell). To do this, I need to be able to pass a parameter to Hyper to specify which terminal I want to start. I don't really mind if I can directly specify the 'shell' value, or if I can specify the path to a specific .hyper.js config file for Bash, CMD, PowerShell, etc.

I took a look through the issues and I didn't see anything like this request in there, so apologies if something similar has been asked before.

The issue names .hyper.js and asks for startup selection among Bash, CMD, and PowerShell. Start by tracing how Hyper reads .hyper.js and handles application startup arguments; done means separate launch shortcuts can select each requested terminal without changing the shared configuration.