Update groonga to 4.0.0.

Release 4.0.0 - 2014/02/09
--------------------------

* Bump version to 4.0.0!

Improvements
^^^^^^^^^^^^

* [normalizer] Supported to show "checks" which is used for calculating next character position.
  Use WITH_CHECKS flag to enable this feature.
* [deb] Dropped Ubuntu 13.04 support.

Fixes
^^^^^

* Fixed a crash bug that an object in grn_expr is used after it is freed.
  Normally Groonga server users aren't affected this bug. This bug mainly affects Rroonga users.
  Because this bug is occured by specifying column name including pseudo column name -
  such as '_key' - Rroonga users may use the usage.
* Fixed not to execute unexpected cascade delete which is introduced Groonga 3.0.8 release.
  If source's range and index's domain are different, Groonga doesn't execute cascade delete.
  [groonga-dev,02073] [Reported by yoku]
* Fixed not to publish grn_snip structure. Use grn_obj instead of grn_snip.
  If you use grn_snip_close, please replace grn_snip_close to grn_obj_close.
* [snippet_html] Fixed a crash bug when --query is empty.
  [groonga-dev,02097] [Reported by Naoya Murakami]
* [snippet_html] Fixed to suppress ALERT level message when contents of column is empty text.
  [groonga-dev,02097] [Reported by Naoya Murakami]
* [groonga-httpd] Fixed a bug "off" is used as path name in groonga_query_log_path.
  [groonga-dev,02113] [Reported by Ryoji Yamamoto]

Thanks
^^^^^^

* yoku
* Naoya Murakami
* Ryoji Yamamoto
Updated textproc/groonga to 4.0.0
Not a "root", it's really fhajny!
Needs gmake. Not MAKE_JOBS_SAFE.