Make name the first argument to Pattern() init

Major incompatibility with previous versions!!

masque/pattern.py

@@ -40,10 +40,10 @@ class Pattern:
     name: str
 
     def __init__(self,
+                 name: str = '',
                  shapes: List[Shape] = (),
                  labels: List[Label] = (),
                  subpatterns: List[SubPattern] = (),
-                 name: str='',
                  ):
         """
         Basic init; arguments get assigned to member variables.