Fix Vector2.Json serialization only loading x value when supplying string as json object and not number array. Also updated function summaries that said "vector4" instead of "vector2" Vector2Int and Vector3Int values now serialize to/from JSON properly. Resolves Facepunch/sbox-issues#5821 Created Vector2Int/Vector3Int ControlWidgets. Resolves Facepunch/sbox-issues#5606