Bump up version number to 3.05

% make update-version NEW_VERSION_MAJOR=3 NEW_VERSION_MINOR=0 NEW_VERSION_MICRO=5
Fix a bug that three or more sections case in W pragma doesn't work

fixes #1770

Reported by shizuin. Thanks!!!
add warnings for date data truncated by mroonga. refs #1768
Fix build error on MySQL 5.6.12

MYSQL_ERROR was ranamed to
Sql_condition since MySQL 5.6.
Ignore an auto generated file
Support MySQL 5.6.12

Reported by WING. Thanks!!!
doc en: add documentation about troubleshooting
doc en: update po
doc: translate po
doc: make documentation more concrete description