Fix Eclipse .classpath: sources, JRE and GAE

Remove class path entries for package directories, which Eclipse
complains about.  Use whatever version of the JRE, rather than
specifying one.
Fix XML validation errors/warnings

Fix schema location in jdoconfig to match namespaced elements.  Add
DOCTYPE declarations (sans DTD) to jdoconfig and appengine-web files to
suppress Eclipse "No grammar constraints" warnings.
Add explicit ordering to future and past events
HTML-ified linky filter and linkified descriptions