Remove splash screen and fix loading issue

[joeyballentine]

The splash screen ended up being pretty easy to replace.

The splash screen getting stuck though was simply because the backend ready event was not being sent through webcontents for some reason, so the listener for it on the frontend wasn't triggering.

[RunDevelopment]

Is seems like the renderer is trying to connect to the backend before realizing that it has to setup the backend on first start up.

The menu is active during loading. I think it would probably be best to completely hide the menu while the renderer is loading.

[joeyballentine]

Honestly I don't believe you that it's this PR that caused that, but I'll look into it anyway

[joeyballentine]

See #2748

[joeyballentine]

Since the issue is unrelated, is this good to merge now?

[RunDevelopment]

Is seems like the renderer is trying to connect to the backend before realizing that it has to setup the backend on first start up.

This is still an issue. We just can't see it with npm start or npm run dev because the renderer takes too long to show up. Make a portable zip of chainner, and this will happen for every fresh install.

[joeyballentine]

fixed

[joeyballentine]

nvm, its not ready. it hangs on subsequent opens... :(

[joeyballentine]

fixed

[RunDevelopment]

fixed

I verified that it behaves correctly now. My comments are just about code quality and other minor things.