updating the OroCronBundle documentation

* add description for the `oro:cron:integration:sync` command
* add instructions for controlling the job processing daemon
* add documentation for job queues
Localization chapter review
fix Nginx syntax highlighting

* use the proper configuration language
* fix syntax error (terminate directives with semicolons)
Added article "How to make import faster".
Added article "How to make import faster".
Added article "How to make import faster".
Added article "How to make import faster".
Add article "How to make import faster"
 - CR fixes
Add article "How to make import faster"
 - CR fixes
Add article "How to make import faster"
 - CR fixes
Merge pull request #57 from orocrm/cookbook/how_to_make_import_faster

Added article "How to Accelerate Import". From the English POV everything is OK
Merge pull request #55 from xabbuh/fix-nginx-code-block

fix Nginx syntax highlighting
limit the table of contents to two levels
update the todo list

Removes tasks that have already been done and are part of the publicly
accessible documentation.
Merge pull request #65 from xabbuh/user-guide-limit-toc

limit the table of contents to two levels
Set latest release version.
Merge pull request #49 from xabbuh/jobs-update

updating the OroCronBundle documentation
Merge pull request #54 from xabbuh/localization-review

Localization chapter review
Merge pull request #66 from xabbuh/update-todos

update the todo list
Update how_to_accelerate_import.rst