Add very verbose option (#24)

Pytest has an option for higher verbosity, which will display the full diff for objects that fail equality assertion (-vv). In my work, I've found the flag to be indispensable for TDD. This PR adds the -vv flag as an option in the magit popup menu using the -w flag.

Co-authored-by: Ryan Pilgrim <[email protected]>

Author: r-zip

python-pytest.el

@@ -133,6 +133,7 @@ When non-nil only ‘test_foo()’ will match, and nothing else."
     (?s "do not capture output" "--capture=no")
     (?t "do not cut tracebacks" "--full-trace")
     (?v "verbose" "--verbose")
+    (?w "very verbose" "-vv")
     (?x "exit after first failure" "--exitfirst"))
   :options
   '((?k "only names matching expression" "-k")