Update deps

+ specs 2.3.4 -> 2.3.7
+ akka 2.2.0 -> 2.2.3
+ commons-codec 1.7 -> 1.9. See http://commons.apache.org/proper/commons-codec/changes-report.html
+ joda-time 2.2 -> 2.3. Full compatible. See http://www.joda.org/joda-time/upgradeto230.html, http://upstream-tracker.org/java/versions/joda-time.html
+ joda-convert 1.3.1 -> 1.5. See http://www.joda.org/joda-convert/changes-report.html
+ jackson 2.2.2 -> 2.3.1 (core) & 2.3.0 (databind, annotations). See https://groups.google.com/forum/#!topic/jackson-dev/3kBEjIBvqYw
+ async-http-client 1.7.21 -> 1.7.23