Reorganization of  existing docs.
some fixes
some more docs fixes
refactoring of the tutorial topic
Tutorial article finished

2 examples developed, the simplest with stdout and more complex file
logging.
Drafts for many articles added
Added new articles

- Attritube mapping
- Message filtering
- Elasticsearch sink description
- Some minor editions
Multiple editions
Bugfixes
Some correction for more precision.
Merge pull request #31 from BayoNet/master

[Documentation] Update.