MAINT switch master __version__ to 0.20.dev0
@@ -109,7 +109,7 @@ warnings.filterwarnings('always', category=DeprecationWarning,
# Dev branch marker is: 'X.Y.dev' or 'X.Y.devN' where N is an integer.
# 'X.Y.dev0' is the canonical version of 'X.Y.dev'
#
-__version__ = '0.19.dev0'
+__version__ = '0.20.dev0'
try:
