mega-manual: Updates to support BitBake User Manual

Fixes [YOCTO #12399]

Fixes made to have the BitBake User Manual included in the build
of the mega-manual.  I placed this manual at the end of the
mega-manual.  Following changes made:

 * Makefile - Modified to include two PNG files.  All PNG files
              in a given manual are listed in the area that makes
              the mega-manual so that the tarfile is complete.

 * mega-manual.xml - Updated the front wording to tell the user
              that the BitBake User Manual is included in the
              Mega-Manual.  Also, added a last section to actually
              include the bitbake-title.png file and the *.xml
              files.  Note that I could not add the title figure
              from the same figures folder of the local "bitbake"
              folder.  Would not include in the build.  So, I
              pulled the file from the figures folder of the
              mega-manual, which is what I do for all the other
              book titles used in the mega-manual.

 * mega-manual.sed - Modified to clean out the old stuff that
              had been carried along for older books not
              supported for the release.  Modified to include
              link processing for the newly included BitBake
              User Manual.

 * New Figures - Moved copies of the "bb_multiconfig_files.png"
              and "bitbake-title.png" figures into the
              figures folder of the mega-manual.

(From yocto-docs rev: 78a1ae0ca92bb7f8a9d3a32a320299371d0ed361)

Signed-off-by: Scott Rifenbark <srifenbark@gmail.com>
Signed-off-by: Richard Purdie <richard.purdie@linuxfoundation.org>

documentation/mega-manual/mega-manual.xml

@@ -12,9 +12,11 @@
 
         <abstract>
             The Yocto Project Mega-Manual is a concatenation of the published
-            Yocto Project HTML manuals for the given release.
-            The manual exists to help users efficiently search for strings
-            across the entire Yocto Project documentation set.
+            Yocto Project HTML manuals along with the corresponding BitBake
+            User Manual for the given release.
+            The Mega-Manual exists to help users efficiently search for strings
+            across the entire Yocto Project documentation set inclusive of
+            the BitBake User Manual.
         </abstract>
 
         <mediaobject>
@@ -322,6 +324,30 @@
     <xi:include
         xmlns:xi="http://www.w3.org/2003/XInclude" href="../toaster-manual/toaster-manual-reference.xml"/>
 
+<!-- Includes bitbake-user-manual title image and then bitbake-user-manual chapters -->
+
+    <para>
+        <imagedata fileref="figures/bitbake-title.png" width="100%" align="left" scalefit="1" />
+    </para>
+
+    <xi:include
+        xmlns:xi="http://www.w3.org/2003/XInclude" href="../../../bitbake/doc/bitbake-user-manual/bitbake-user-manual-intro.xml"/>
+
+    <xi:include
+        xmlns:xi="http://www.w3.org/2003/XInclude" href="../../../bitbake/doc/bitbake-user-manual/bitbake-user-manual-execution.xml"/>
+
+    <xi:include
+        xmlns:xi="http://www.w3.org/2003/XInclude" href="../../../bitbake/doc/bitbake-user-manual/bitbake-user-manual-metadata.xml"/>
+
+    <xi:include
+        xmlns:xi="http://www.w3.org/2003/XInclude" href="../../../bitbake/doc/bitbake-user-manual/bitbake-user-manual-fetching.xml"/>
+
+    <xi:include
+        xmlns:xi="http://www.w3.org/2003/XInclude" href="../../../bitbake/doc/bitbake-user-manual/bitbake-user-manual-ref-variables.xml"/>
+
+    <xi:include
+        xmlns:xi="http://www.w3.org/2003/XInclude" href="../../../bitbake/doc/bitbake-user-manual/bitbake-user-manual-hello.xml"/>
+
 </book>
 
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