Over the years, the Perforce connection code went through many changes

designed to normalize strings so that we would ensure the Perforce

client would receive byte strings, no matter what was being passed in.

Some of these were no longer necessary, and in fact causing problems, as

None values were getting converted to 'None' text strings, which

could cause problems in very specific edge cases on Perforce deployments

involving clients named 'None' that had restricted client views.
Along with this, these changes were only compatible with Python 2, as

modern versions of Perforce on Python 3 use Unicode strings.
This change removes the unnecessary string conversion when populating

our PerforceClient based on the Repository settings, and updates the

P4 string setting to use the right string type for the right version

of Python.
Unit tests were added to check that both PerforceClient and P4

received the proper values and string types.

Unit tests passed.
Verified connection against real-world servers.
Tested on Review Board 2.5 and 3.0.