Pysigma

Quoting of whitespaces in field names.

What's Changed
* Moved data model mappings to processing pipeline
* Add repository by fabaff in https://github.com/SigmaHQ/pySigma-backend-splunk/pull/3
* Added initiliazation and condition to avoid UbuoundLocalError by elhoim in https://github.com/SigmaHQ/pySigma-backend-splunk/pull/4
* Updated dependencies

New Contributors
* fabaff made their first contribution in https://github.com/SigmaHQ/pySigma-backend-splunk/pull/3
* elhoim made their first contribution in https://github.com/SigmaHQ/pySigma-backend-splunk/pull/4

**Full Changelog**: https://github.com/SigmaHQ/pySigma-backend-splunk/compare/v0.3.2...v0.3.3

Added common pipeline condition for Windows DNS events.

Import cleanup fixing errors if development dependencies are not installed.

Improved error handling. Location of Sigma rules and their subobjects are now tracked and file with error is shown if available in exception.

* Updated to pySigma 0.5.0
* `field IN (value list)` expressions are now generated with wildcard values.