test: route: add mail_handler test defined at r8162

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@8399 e93f8b46-1217-0410-a6f0-8f06a7374b81
test: route: add 'my' test

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@8332 e93f8b46-1217-0410-a6f0-8f06a7374b81
test: route: simplify "my" tests

git-svn-id: svn+ssh://rubyforge.org/var/svn/redmine/trunk@8366 e93f8b46-1217-0410-a6f0-8f06a7374b81