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

commit: https://github.com/kijiproject/kiji-model-repository/commit/3070dee37dd460c692b4734f2bddf0d49510926d
kiji-model-repository: [maven-release-plugin] prepare release kiji-model-repository-root-0.7.1

commit: https://github.com/kijiproject/kiji-model-repository/commit/10b91679ffeac93b88865dd894fb9e4dcafe1d53