Open Exclusive Regions

Removes gate restrictions and allows exclusive and special gates, such as the ones to Metropolis and Outer Expanse to be opened by any slugcat, as if they were normal gates. Adds back the gate from Subterranean to Outer Expanse for Rivulet and Saint. Adds a new gate from Silent Construct to Metropolis for Saint. Adds a new gate from Subterranean to Rubicon for all slugcats except Saint. Attention! Trying to access the Bitter Aerie gate as Spearmaster will cause the game to freeze! I won't be fixing that for now since I'm focused on the Beecat mod.