Perform basic checks when uploading a new version

[Katrix]

Creating this issue to group together all checks and warnings that should be issued when creating a new release.

• [ ] Check that the dependency versions are not SNAPSHOTs. See #388 for more details.
• [ ] Check that a version contains a valid mcmod.info
• [ ] Check that the version in the mcmod.info and the version name are releated (one contains the other, or they are equal)

Probably supersedes #388