Minor improvements to `VowsReporter.print_traceback()` (in `reporting.common`)
Minor improvements to `VowsReporter.print_traceback()` (in `reporting.common`)

* every time I read “exc_blah”, I think “**execute** blah” instead of “**exception** blah”.  So I renamed these to “err_blah”. :-P
* Also renamed `err_value` to `err_obj`, since it more accurately describes what the variable contains
* Also, this method was manually indenting its output; changed to use the `indent_msg()` method

heynemann/pyvows,marcelometal/pyvows