Corrected a number of pep8 errors

 * E128 continuation line under-indented for visual indent
 * F402 import 'u' from line 23 shadowed by loop variable
 * H202 assertRaises Exception too broad
 * H305 imports not grouped correctly (re: stdlib, six: third-party)
 * H307 like imports should be grouped together (six and oslo.config.cfg from third-party are separated by whitespace)
 * H405 multi line docstring summary not separated with an empty line
 * H904 Wrap long lines in parentheses instead of a backslash

Change-Id: If2eb58b9a54198e7b9e81e213742f5759515ef8f
Merge "Corrected a number of pep8 errors"