user-manual-intro.xml: Trying to fix up the headings.

Trying to fix up the section tags to make the compile work
properly.

Signed-off-by: Bill Traynor <wmat@alphatroop.com>
user-manual.xml: Fixing up include statements.

Trying to get the new files to include properly.

Signed-off-by: Bill Traynor <wmat@alphatroop.com>