Wrap tag munging code in config option, defaulting to False.
Removed extra newline.
Config option to munge tags changed to be consistent with other config options in this extension, and noted in README.
Moved clean_tags check into _create_or_update_package method.
Merge branch 'ogdch-79-optional-tag-munging'
[#83] Fix key error when using default_groups
[#84] Fix auth audit exception when creating datasets

This was caused by a combination of the auth audit leaking and the
harvester reusing the context for the package_show and package_create
actions. If the package is not found, package_show does not call
check_access, and the auth audit does not pass. This is stored in the
context (`__auth_audit`) and is raised next time that we call
get_action (when we call package_create with the same context)

It could potentially be fixed on master, but it is probably quite rare.
[#80] Support for Python 2.6 when handling xml exceptions
[#87] Remove remote url_type from resources

Otherwise CKAN thinks they are uploads, datastore resources, etc, which
it can cause problems eg when displaying the URL of the resource. We
are just linking to the remote resource URL.
[#86] Fix duplicate extras