setup.py: move from dict() construction to {} literals

The latter are both faster and more consistent across Python 2 and 3.

setup.py

@@ -554,9 +554,11 b" setup(name='mercurial',"
       package_data=packagedata,
       cmdclass=cmdclass,
       distclass=hgdist,
-      options=dict(py2exe=dict(packages=['hgext', 'email']),
-                   bdist_mpkg=dict(zipdist=True,
-                                   license='COPYING',
-                                   readme='contrib/macosx/Readme.html',
-                                   welcome='contrib/macosx/Welcome.html')),
+      options={'py2exe': {'packages': ['hgext', 'email']},
+               'bdist_mpkg': {'zipdist': True,
+                              'license': 'COPYING',
+                              'readme': 'contrib/macosx/Readme.html',
+                              'welcome': 'contrib/macosx/Welcome.html',
+                              },
+               },
       **extra)