Update plexus compiler versions and doclint settings to make Jimfs build under JDK8.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=79360036
Add build status to README.
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Created by MOE: http://code.google.com/p/moe-java
MOE_MIGRATED_REVID=79427380