Distinguish mysql/mysql2 adapters in Gemfile (#13270).

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@11494 e93f8b46-1217-0410-a6f0-8f06a7374b81
Don't reload the issue in after_save callback.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@11495 e93f8b46-1217-0410-a6f0-8f06a7374b81
Code cleanup.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@11496 e93f8b46-1217-0410-a6f0-8f06a7374b81
Fixed that #reload raises a Stack too deep error with ruby 2.0.

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@11497 e93f8b46-1217-0410-a6f0-8f06a7374b81