feat: Remove version (highRes, lowRes) differentiation

[Tandashi]

Moving forward the Steam Release version will only have one Version. In addition you now select the base folder or the downloaded content. No more custom path / game structure.

Further more the version.txt code has been removed as well since Steam will be responsible for updates if there every should be any.

[Ipmake]

Would it be better if we move this to its own branch for now "version2-steam"?

[Tandashi]

Will create a new Pull Request with Steam support.