Switch the Tomcat 8 and Jetty 9 samples to Tomcat 7 and Jetty 8. Since
Tomcat 8 and Jetty 9 are now the default versions the previous samples
are no longer relevant, however, we do need integration tests to check
that we remain compatible with Tomcat 7 and Jetty 8.
See gh-1832
Long package names are really unnecessary in samples and they
just clutter things up. Also Spring Loaded doesn't work with
org.sfw packages, so to demo that technology you need a
different package name.
Fix TomcatEmbeddedServletContainerFactory to set a MERGED_WEB_XML
attribute when JSPs are used. This is required for EL support with
JSPs since Jasper checks the version number in the web.xml. Without
any web.xml Jasper default to disabling EL.
Issue: #55752948