Coding standards and style refactor of runner

* Reordered imports
* Replaced all instances of the use of % style string formatting
  with python 2.6 compatible .format() string formatting.
* Removed the use of  newline escapes on line breaks and stacked
  paramaters where they did not increase readability.
* Removed redundant try-excepts.
* Refactored tag and attr checking methods to remove the use of
  eval()

Change-Id: Iaa4dee234b223526310b1ec1123492e8f5e296e3
Merge "Coding standards and style refactor of runner"