document how to "turn off" log levels
breakup contextInitialized() into smaller methods

Each method is protected so subclasses can override them. This lets subclasses customize what's done or skip it altogether (by making the overridden method do nothing).
fix bug where we incorrectly determine Sun/Oracle JRE

Java 7 reports the java.vendor System property is "Oracle Corporation".
See https://blogs.oracle.com/kto/entry/jdk7_pending_java_vendor_property
Merge pull request #24 from bradcupit/refactored-init

Refactored contextInitialized(), improved/fixed Oracle JRE detection and documentation.
Bring to base java 6 support

Use java 6 as starting point rather than java 5.  POM was missing
setting to do this but contained code that was java 6 based.

Added standard git attributes.
Added missing git ignores.
Updated dependencies that do not affect leak detection.
Fix majority of warnings generated out of ClassLoaderLeakPreventor even
if most are <?>.