Fixes gh-438

Fixes gh-417

RC4 added a ServletRegistrationBaen for teh DispatcherServlet and we
didn't register a MultipartConfigElement if one was present.

Fixes gh-427

Fixes gh-424

Fixed gh-428

Fixes gh-430

Fixes gh-433

... leaving only the embedded Tomcat enabling feature (registering
the WsSci).

Fixes part of gh-65

* patch-2:
  Correct link to samples.

Fixes gh-415

Rename ErrorWrapperEmbeddedServletContainerFactory to ErrorPageFilter
and extend AbstractConfigurableEmbeddedServletContainer rather
than AbstractEmbeddedServletContainerFactory.

Fixes gh-416

Rename ConfigurableEmbeddedServletContainerFactory to
ConfigurableEmbeddedServletContainer and extract
AbstractConfigurableEmbeddedServletContainer from
AbstractEmbeddedServletContainerFactory.

Update ConfigurableEmbeddedServletContainerFactory to no longer directly
extend EmbeddedServletContainerFactory.

Remove getPort() from ConfigurableEmbeddedServletContainerFactory to
keep the interface primarily setters.

There's no explicit support for older Servlet specs in Spring Boot,
but we can at least make it easy for others to provide such
support by not adding stuff to the context when in an older container.

Useful sample for common use case where user adds custom Authentication,
a form login, *and* global method security all the the same application.

Some assumptions were being made in tests, e.g. about
there being an AuthenticationManager @Bean, which were
false with the new Security 3.2.1 updates from Rob.

Also parent-child contexts with the actuator were
problematic because they didn't exclude the web configuration
for the management security in the parent context.

Fixes gh-244

Also change strategy for defaulting of Authentication. Spring
Boot authentication defaults are now encapsulated and can easily
be overridden by a user defined AuthenticationManager.

Error pages are a feature of the servlet spec but there is no Java API for
registering them in the spec. This filter works around that by accepting error page
registrations from Spring Boot's EmbeddedServletContainerCustomizer (any beans
of that type in the context will be applied to this container).

In addition the ErrorController interface was enhanced to provide callers
the option to suppress logging.

Fixes gh-410

Fixes gh-411

Fixes gh-60

User can then use a weak reference map (for instance), if worried
about memory usage.

Fixes gh-405

Hibernate is picky about javassist, but unfortunately that
library is used by other parts of our stack (Thymeleaf!?), so
we need a policy for resolving the dependency transitively.
I fixed it to the version in Hibernate 4.3.1 (our current
best foot forward), but it will have to be updateed whenever
Hibernate is.

Fixes gh-402