Site configuration

[stefanalund]

Introduce a site config file (example) so that people deploying Backstage can customize things like:

• Site name (everyone may not want to use "Backstage")
• Site logo
• Proxy URLs etc
• Timezones for Homepage headers
• GitHub URL
• ...

[Rugvip]

We probably want to expose most of these through APIs in core, but also want to identify if there are any parameters that can't be configured there.

Example of a possible solution for how to configure the site name would be

createApp({
  name: 'Backseat',
})

[andrei-pavel]

through APIs

That's written correctly. Maybe fix it in the pretty image in the README too? Sorry, I'll go now, bye!

[Rugvip]

Closing this as work done towards #1012 has become the solution for this. If we want to add individual configuration values I think we should open up separate issues where we can discuss those.