license: Update license for gnovm and gno.land

[jaekwon]

This is a continuation of #397.

This is the Gnu GPL license and AGPL licenses (both version 3), converted into the Gno GnoPL and Network GnoPL licenses.

The merging of this PR will change the license. Do not merge until the following is complete:

• Add strong attribution terms as "additional terms" for competitors to gno.land, to be defined as any blockchain or service that uses a blockchain where users can deploy their own smart contracts either by uploading smart contract code or choosing them from an app store.

Strong attribution here means not only giving us the standard attributions in code, but also in the main README, and also in the primary portal interface for users to prominently link to gno.land, for example on the top right corner in the header bar.

[moul]

Do not merge.

[jaekwon]

Merging now, because it's been too long and something is better than nothing.
The spirit of what is intended is described here.
Additional context for why strong attribution is required, is described in
AIB's two announcements:

• https://github.com/allinbits/announcements/blob/main/2023_03_01_response.md
• https://github.com/allinbits/announcements/blob/main/2023_03_24_legalaction.md

The next step will be to double check and clean errors if any, and to modify the
strong attribution terms of the gno vm (but not gno.land) to also require similar
strong attribution for any gno IDEs.