Merge pull request #147 from mihai-chezan/dev

Close connectons async.
Minor performance tuning to avoid excessive connection attempts of downed databases.
Fixed #148 revert to using LinkedList rather than FastList in ConcurrentBag due to Tomcat leak detection.
Fix potential (but never encountered) NPE
Fixed #148 remove static ThreadLocal, causes a regression with multiple-pools.
Updated change log.
Simple variable renames for clarity.
Simple variable renames for clarity.
JavaDoc fixes.
Fixed #147 Integrate close asynch change into java6 code.
Switch from LinkedList to ArrayList.
Include exception in rethrow.
Update README.md
Update README.md
Make members final.
Merge branch 'dev' of github.com-brettwooldridge:brettwooldridge/HikariCP into dev

* 'dev' of github.com-brettwooldridge:brettwooldridge/HikariCP:
  Update README.md
  Update README.md
Fixup OSGi bundle.
Expose metrics through the HikariDataSource.
Change metrics names to omit class name.
Fix issue with improper initialization of lastAccessTime.