Fixes gh-470

We had been making a special case for logback.xml anyway, so
extending that to simply deleting recursively all of
src/main/resources (or equivalent) from target/classes (or
equivalent) seems like it's perfectly justifiable.

Fixes gh-451

The management.contextPath property should now be respected in a
secure application, whether or not the management.port is different.

Added some test cases in the sample to verify.

Fixes gh-469

Boot promotes the use of a templates directory for housing view
templates. Include this directory by default when building a jar file
from a CLI app.

Fixes #455

Fixes gh-463

Explicitly link to install.txt in source repo to avoid issues on projects.spring.io with a broken relative link
... also fix this for rendered markdown on GH itself :-)

Use org.springframework.boot instead of ${project.groupId}
groupId in order to make it easier to use spring-boot-samples
modules as a starting point for new projects.

Fixes gh-447

This turns out to affect JPA, but only because it looks for a URL for the
root of the classpath using ClassLoader.getResource("") which barfs in
an app launched from an executable JAR. It's easy to make a special case
for "" in the class loader, so I went ahead and did that. Possibly need
to think what the implication of getResources("") is as well (not
tested in an app yet).

Fixes gh-420

Fixes gh-441

Profiles set with Environment.setActiveProfiles() (rather than
spring.profiles.active) *before* any config files are processed, are
treated as "additional" (to the ones supplied in spring.profiles.active
from all sources, files and System properties included).

Fixes gh-429

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.