add additional metadata

[DerMolly]

There are some more metadata tags as mentioned in #11. I added the ones that are there by default if you create a new game in tic-80, but we should probably include menu and strict as well at some point…

[chronoDave]

Thanks for opening the PR, as mentioned in #11, would you happen to have a source for these metadata changes?

[DerMolly]

As mentioned they are present, when you create a new game in a current version of TIC-80. Not sure if it's explained elsewhere. The documentation that is linked README.md was not updated, which it probably should be.

[chronoDave]

If you could update the link to point to https://github.com/nesbox/TIC-80/wiki/Cartridge-Metadata instead, that'd be great.

Looking through that wiki page and scouring through TIC-80's repo, I struggle to find how and where these metadata values are used. The most recent demo seems to be janetdemo.janet which does include site and license as you've added, but also a missing field strict.

Given the lack of documentation, would you say it would be better for tic-bundle to support additional custom tags?

{
  metadata: {
    ...
    mycustomtag: 'mycustomvalue'
  }
}

--mycustomtag: mycustomvalue

[DerMolly]

I think that would be a good solution to the problem at hand. Question is should this be in addition to this PR? Or instead of? What do you think?

[chronoDave]

Can be a separate PR as it falls outside the scope of this PR. I've created an issue for it: #19

Given that the tags you've added are available in TIC-80 demo files I'm alright with merging them. Only request I have is removing the default value for license as mentioned prior.