Tabify pom
Checkstyle changes

Allow tabs, RightCurly alone, ignore javadoc for now
Update versions of maven plugins
Use same config for findbugs for site
Upgrade caliper to 1.0-beta-1
Add maven enforcer
Bad version for maven-checkstyle-plugin

maven-checkstyle-plugin uses checkstyle 5.6 which removed
the DoubleCheckedLocking check
Resolve all checkstyle errors