Update to bashate 0.5.1

This minor release of bashate just fixes one small issue with python3
compatability.  This is an alternative to
Ic91b5ce8cb85e376573f9bf3659d2a86cc437179.

Change-Id: Ie5ad29003cf80a332b9a9258749757a15de79966

Author: ianw

tox.ini

@@ -12,7 +12,7 @@ install_command = pip install {opts} {packages}
 # against devstack, just set BASHATE_INSTALL_PATH=/path/... to your
 # modified bashate tree
 deps =
-   {env:BASHATE_INSTALL_PATH:bashate==0.5.0}
+   {env:BASHATE_INSTALL_PATH:bashate==0.5.1}
 whitelist_externals = bash
 commands = bash -c "find {toxinidir}             \
          -not \( -type d -name .?\* -prune \)    \