Use just one flake8 file; mark package.py files to avoid E501 w/url.

.flake8

@@ -0,0 +1,12 @@
+# -*- conf -*-
+[flake8]
+# Descriptions of ignored checks:
+#
+# E221: multiple spaces before operator
+# E241: multiple spaces after ‘,’
+# F403: disable wildcard import
+# F821: undefined name (needed for build commands)
+# F999: Undefined undefined name (needed for build commands)
+#
+ignore = E221,E241,F403,F821,F999
+max-line-length = 79