kiji-mapreduce: [maven-release-plugin] prepare release kiji-mapreduce-root-1.2.4

commit: https://github.com/kijiproject/kiji-mapreduce/commit/afc16a7c4f4368e8f52c5a9a08c77e2c4ef53ed1
kiji-mapreduce: [maven-release-plugin] prepare for next development iteration

commit: https://github.com/kijiproject/kiji-mapreduce/commit/a354a62fceadb539cd604c686fd46ea3b6472ef6