Helper script for running gpgbridge

[mhyllander]

Thank you to @tetov for the contribution of a helper script to run gpgbridge. I made some smaller modifications due to changes I made in gpgbridge, and updated the documentation.

[tetov]

Sorry, I've been a bit busy. But there's some errors in the setup I proposed. Something about needing to source the script, and you can't pass arguments when you source something. Have you tested this? My quickfix was to export arguments as variables and then source..

[mhyllander]

Well, same here. But actually your helper script works well. You just run it as an ordinary script, no sourcing needed. I tested it and made some minor adjustments, that's all.

[mhyllander]

@tetov Actually you were right, there was a problem. But it is that the start_gpgbridge function needs to export the SSH_AUTH_SOCK environment variable, and it can't do that from a sub-shell. So the script file needs to be sourced. I fixed it in #13 by moving the args parsing into the start_gpgbridge function instead, so you can call start_gpgbridge --wsl2 --ssh after sourcing the file.