annotations: POM-40. Require JDK 7 to compile Kiji projects

issue: https://jira.kiji.org/browse/POM-40
review: https://review.kiji.org/r/2012
commit: https://github.com/kijiproject/annotations/commit/a19a0523de708d806e3099f9129c49dabac63816
annotations: [maven-release-plugin] prepare for next development iteration

commit: https://github.com/kijiproject/annotations/commit/6218682168ef275e3ba51fa495d30dda7de54c98
annotations: [maven-release-plugin] prepare release annotations-1.1.0

commit: https://github.com/kijiproject/annotations/commit/2bc58ec9ca1a0f88971c0369c1ff6577e58b26e6