Glasswall

- Symbolic link fixes in `glasswall.utils.list_file_paths`
- Add ArchiveManager `is_supported_archive` method (ArchiveManager >= 0.45)
- Fixed a bug when attempting to create custom content management policies.
- Fixed an uninitialised variable bug for memory to memory file management mode in ArchiveManager and WordSearch.
- Added more logging, restructured logging messages to be more consistent across products.
- Modified many logs from warning level to error.

Added a staticmethod for Policy objects: `from_string` to create a Policy object from a string representation of an xml content management policy, or from a file path.

Adds new functionality to Archive Manager wrapper:
- export
- export_directory
- import
- import_directory

Also contains an additional bug fix for sysConfig within archiveConfig.

Fixes a bug with `sysConfig` containing the switch default="sanitise".
Fixed a bug where attributes of an `archiveConfig` could not be set.

Fixes an inconsistency in the analysis functionality between file management modes when used with a disallow content management policy.

* The `analyse_directory` and `protect_directory` functions of Archive Manager are now consistent in the use of the `output_report_directory` argument.
* Improved Archive Manager documentation and logging.