A little more work on python logging
A little more work on python logging

-- Changed the initialization code for WeaveStack so that a default log handler is only
installed if no other handler is in place at any point in the logger hierarchy. Now, if you
initialize the root logger prior to initializing WeaveStack, openweave log output will
naturally go to the root handler, whereas if you don’t, output will go to stdout by default.

openweave/openweave-core,openweave/openweave-core,openweave/openweave-core,openweave/openweave-core,openweave/openweave-core,openweave/openweave-core