Use ANONYMOUS user constant from Errai Security.
Removed all dependencies on UF types (fixes Eclipse JDT APT bug)

See comments in https://bugs.eclipse.org/bugs/show_bug.cgi?id=280542 for details
Removed slf4j because it sometimes breaks under eclipse JDT. Now all logging is done via the official Messager API.
Cleaned up some usages of GenerationException and added a note saying not to use it for new stuff
Disabled logging inside Freemarker; its attempt to initialize inside JDT was causing ExceptionInInitializerError
maven-shade-plugin version 2.2 works under Maven 3 (inherited managed version 2.0 does not)