Upgrade to Surefire 2.18

Notably this addresses SUREFIRE-1028 which prevented running single
test methods.

Changelog:

http://mail-archives.apache.org/mod_mbox/maven-announce/201411.mbox/%3CCAK2FUK2o_9oAUcWkAC=pbA5vejMKW0i0Pn9XBBo9cTg2uRFRYg@mail.gmail.com%3E
Upgrade to assertj 1.7.0

Release notes:

http://joel-costigliola.github.io/assertj/assertj-core-news.html#assertj-core-1.7.0
Upgrade to commons-codec 1.10

Changelog:

http://commons.apache.org/proper/commons-codec/changes-report.html#a1.10
Upgrade to JUnit 4.12

Release notes:

https://github.com/junit-team/junit/blob/master/doc/ReleaseNotes4.12.md