Warn when downgrading dependency mod

[GeckoEidechse]

When installing a mod with a dependency that requires an older version of said dependency than what is already installed, we should show a warning and/or option not to downgrade.

[GeckoEidechse]

Maybe we should even show a warning if two mods use a dependency of a different version.

If we assume everyone adheres to semver, we would only have to show the warning on different major version and otherwise just stick to the newer out of the two versions.