[tut/chap6] clarified scope of reorg, added figure, etc.

- Clarified the scope of the refactorings/reorg.
- Added figure to show how the search template HTML was migrated into
the search component template file.
- Some edits to match the code.
- Copy edits.
[tut/chap6] fix suggested by Kathy
[Chap 6] missing commas
[Chap 6] copyedit following Kathy's feedback
[Chap6] avoid switch in subject
Improvements based on Kathy's feedback & made 3-part table narrower
Fixed alt text for img/ch06-1-QueryServiceOutline.png
Merge pull request #15 from chalin/patch-chap6-edits

[tut/chap6] clarified scope of reorg, added figure, etc.