For compatibility with Gradle docbook-reference-plugin, which cannot
handle DocBook 4.

This change eliminates the spring-framework-reference subproject, moving
these sources into the root project's own src directory.

This makes sense because the reference docs span all submodules, and
also because api Javadoc is created at the root project level as well.
This means that both api and reference documentation output will now
reside in the root project's 'build' directory. This is more consistent
and easy to discover.

aspectjrt is a subset of aspectjweaver. Eliminate mentions of aspectjrt
where aspectjweaver is already necessary (e.g. LTW), and do not mention
aspectjweaver where only aspectrt is required (e.g. @Aspect proxying)

Also bump required version of aspect* libs from 1.5 to 1.6.8, reflecting
OSGi and pom metadata.

Issue: SPR-8896

Issue: SPR-7788, SPR-6575

Updating references to @resource usage

Issue: SPR-8268

docs for LTW for WebSphere

+ add note about JBoss 6

Also change 'JEE' -> 'Java EE'

SPR-7161
+ update Petclinic references
+ minor corrections

+ added some clarifications
+ improved the document structure

SPR-6756

updated reference documentation with references to "spring-agent.jar" to use "org.springframework.instrument-{version}.jar" (SPR-6597)

+ renamed spring-agent.jar to org.springframework.instrument.jar through-out the documentation.

+ most of the problems were already fixed (probably by Mark). These are just minor adjustments

* eliminated all usage of "the section entitled", because <xref> links already render including "the section called ".  This was resulting in sentences like 'see also the section entitled the section called "@Autowired"'. This issue affected nearly all sections of the documentation, so went beyond just beans.xml

* fixed table overflow in the "Using filters to customize scanning" section (approx. p.90)

* fixed all code overflows in <programlisting/> elements

* corrected a couple minor syntax errors with SpEL examples (missing closing braces)

* added 'language="..."' element to <programlisting> elements where appropriate to enable syntax highlighting.

* normalized all code indention to four-space (some code listings were using one- and two-space)

* updated all code listings to use same-line opening braces.

* eliminated section regarding backward compatibility with Spring DTDs and singleton=true|false.  This seems like cruft to me, and we shouldn't keep historical notes around forever.

* Added <note> regarding the new thread scope (SimpleThreadScope) to Section 3.5 Bean Scopes.  Also updated the section on registering a custom Scope implementation to use the SimpleThreadScope as an example.

* updated the new-in-3.xml section to improve the @Configuration example