[maven-release-plugin] prepare release mailsender-1.7.4

git-svn-id: https://source.sakaiproject.org/svn/mailsender/branches/1.7@128827 66ffb92e-73f9-0310-93c1-f5514f145a0a
[maven-release-plugin] prepare for next development iteration

git-svn-id: https://source.sakaiproject.org/svn/mailsender/branches/1.7@128829 66ffb92e-73f9-0310-93c1-f5514f145a0a
Jenkins post-build: Auto-updating master version to 2.9-SNAPSHOT for next release http://builds.sakaiproject.org:8080/job/mailsender%201.7.x/

git-svn-id: https://source.sakaiproject.org/svn/mailsender/branches/1.7@128830 66ffb92e-73f9-0310-93c1-f5514f145a0a