types: add missing MapTypes. all stock GMFs now parse correctly

gmflib/src/types.rs

@@ -136,6 +136,8 @@ impl gma::Serializable for MapKind {
 pub enum MapType {
     Explicit = 0,
     Spherical = 1,
+    Cylindrical = 2,
+    Shrinkwrap = 3,
     Screen = 4,
 }