Add swsh placeholders

no point adding for legality until much closer to game release

PKHeX.Core/Game/GameUtil.cs

@@ -84,6 +84,10 @@ public static GameVersion GetMetLocationVersionGroup(GameVersion Version)
                 case GP: case GE:
                     return GG;
 
+                // Gen8
+                case SW: case SH:
+                    return SWSH;
+
                 default:
                     return Invalid;
             }
@@ -230,6 +234,10 @@ public static bool Contains(this GameVersion g1, GameVersion g2)
                 case Gen7:
                     return SM.Contains(g2) || USUM.Contains(g2) || GG.Contains(g2);
 
+                case Gen8:
+                case SWSH:
+                    return g2 == SW || g2 == SH;
+
                 default: return false;
             }
         }

PKHeX.Core/Game/GameVersion.cs

@@ -192,6 +192,16 @@ public enum GameVersion
         /// Pokémon Let's Go Eevee (NX)
         /// </summary>
         GE = 43,
+
+        /// <summary>
+        /// Pokémon Sword (NX)
+        /// </summary>
+        SW = 44,
+
+        /// <summary>
+        /// Pokémon Shield (NX)
+        /// </summary>
+        SH = 45,
         #endregion
 
         // The following values are not actually stored values in pkm data,
@@ -332,9 +342,9 @@ public enum GameVersion
         /// <summary>
         /// Pokémon Omega Ruby &amp; Alpha Sapphire version group.
         /// </summary>
+        /// <remarks>Used to lump data from the associated games as data assets are shared.</remarks>
         /// <see cref="OR"/>
         /// <see cref="AS"/>
-        /// <remarks>Used to lump data from the associated games as data assets are shared.</remarks>
         ORAS,
 
         /// <summary>
@@ -361,6 +371,14 @@ public enum GameVersion
         /// <see cref="GE"/>
         GG,
 
+        /// <summary>
+        /// Pokémon Sword &amp; Shield
+        /// </summary>
+        /// <remarks>Used to lump data from the associated games as data assets are shared.</remarks>
+        /// <see cref="SW"/>
+        /// <see cref="SH"/>
+        SWSH,
+
         /// <summary>
         /// Generation 1 Games
         /// </summary>
@@ -406,8 +424,15 @@ public enum GameVersion
         /// </summary>
         /// <see cref="SM"/>
         /// <see cref="USUM"/>
+        /// <see cref="GG"/>
         Gen7,
 
+        /// <summary>
+        /// Generation 8 Games
+        /// </summary>
+        /// <see cref="SWSH"/>
+        Gen8,
+
         /// <summary>
         /// Generation 1/2 Game Boy Cartridge Era Only
         /// </summary>