Implement Nyan Doom's `GAMEVERS` lump

[PorpiangWriter]

In light of Nugget Doom 4.3.0 being released, I am interested in implementing Nyan Doom's GAMEVERS lump to your Cherry Doom because, well, it is the new fork of DSDA-Doom.

GAMEVERS lump allowing a WAD to further specify a given game version if the COMPLVL value is set to "vanilla", to support the value 1.9, Ultimate, and Final in Cherry Doom, and it also supports the optional Limit Removing with the nolimits value.

[PorpiangWriter]

Nevermind, the Nugget Doom 4.5.0 was released by merging features of the Woof 15.3.0, as Woof partially implements the Nyan Doom's GAMEVERS lump already. But still, you should've released the Cherry Doom 3.0.0 for now.