Added support for clojure 1.5

Removed some? from code and added leiningen profiles to test against
both 1.5 and 1.6.

Conflicts:
	project.clj
update dependencies

Conflicts:
	project.clj
fixed merge error in 5b48ece
better synchronization in test case
Version 0.12.2
Version 0.12.3-SNAPSHOT