update Central w/ newer versions of Findbugs 2.0.3, Subclipse/SVNKit 1.10.4/1.8.4, SpringIDE 3.5.0.20140401-RELEASE, PMD 4.0.2; fix Orbit URL; remove GWT (JBIDE-16960, JBDS-2869); also update README to include instructions on how to do a full install test of the resulting TP site >> master