Add decorator to disable the ERROR log.
Add logging of errors caught around Amazon API connections.
Move handle_exceptions decorator into utilities module.
Clarify purpose of error handling decorator in name and docstring.
Merge branch 'github19'

This completes github issue 19 to add logging for exceptions
caught when connecting to the Amazon API. Because it adds a
utilities module as well it also includes a small refactor of
an unrelated decorator into that module.