Issue 59 ; updating license header and adding one where missing

Issue 29 ; Tweaked checkstyle configuration and ran eclipse formatter on the java source in examples. Reduced checkstyle errors from 5877 to 1352. Note this commit contains formatting-related changes only, no code changes.

Issue 28; re-adding checkstyle plugin configuration to core, extras, and examples poms, adding sun_checks.xml to src/build/conf in each to enable check configuration

issue#6 add overview.html to javadocs

issue#6 ...

svn merge -r117:HEAD https://piccolo2d.googlecode.com/svn/piccolo2d.java/branches/mavenize-1.3 .

issue#44 comes next...