kiji-modeling: [maven-release-plugin] prepare for next development iteration

commit: https://github.com/kijiproject/kiji-modeling/commit/1ac541f356ec57cc57f53f54693dbb9c12a26e98
kiji-modeling: [maven-release-plugin] prepare release kiji-modeling-root-0.8.1

commit: https://github.com/kijiproject/kiji-modeling/commit/fbb160817f33be70aedf39d0ecda59afe5418a06