com.google.web.bindery:requestfactory POM now is a BOM

Somehow forgot to add the requestfactory-* dependencies in the previous
patch that modified com.google.gwt:gwt, while that one clearly expected
that they'd be defined here.

Change-Id: I4770ac879c3618dc47517fd4b86519df450a9cdf
Revert "Fix Servlet 3.0 initialization in JettyLauncher."

This reverts commit 7dc47a04172ee9da3cac969c47095a1023202832.

GWT devmode needs jetty-8.1.12, and jetty-annotations-8.1.12
depends on org.objectweb.asm-3.1.0, but GWT compiler
depends on a modern org.ow2.asm-5.0.3, thus we cannot
execute simultaneously jetty with annotations in devmode
and codeserver since both share the classpath.

Change-Id: I5727e81267fb9517d2cec8dfc9137e5c8c79fece