Do not force log verbosity level to info

Forcing the log level to info causes pbr to emit status log messages
in a way that breaks commands like "python setup.py --maintainer" and
"python setup.py --name", which are useful when scripting operations
that work on packages.

Change-Id: I6607c96e171f2f8efa89bd701018f4af6ec9c15a

pbr/util.py

@@ -150,9 +150,6 @@ BOOL_FIELDS = ("use_2to3", "zip_safe", "include_package_data")
 CSV_FIELDS = ("keywords",)
 
 
-log.set_verbosity(log.INFO)
-
-
 def resolve_name(name):
     """Resolve a name like ``module.object`` to an object and return it.