Clean up Handbook

A while back somebody awesome forked the PIL Handbook (http://effbot.org/imagingbook/pil-index.htm) to Pillow. IIRC we tried to incorporate the handbook "seemlessly", which apparently meant not using the word "handbook" anywhere. Now that seems confusing, so I'm reorganizing all the handbook content under one section named "Handbook".

This commit:

- Moves guides.rst to handbook/index.rst
- Moves appendices.rst to handbook/
- Removes developer.rst from handbook index.
- Removes porting-pil-to-pillow.rst from handbook index.

Unrelated to the above:

- Shorten title "Porting existing PIL-based code to Pillow" to "Porting"
- Move text "Porting existing PIL-based code to Pillow" to faux sub-header (bold text not sub-header because there's only one section.)

"Porting" may be better named "Migrating", not sure yet.

README.rst

@@ -40,7 +40,7 @@ More Information
 - `Documentation <https://pillow.readthedocs.org/>`_
 
   - `Installation <https://pillow.readthedocs.org/installation.html>`_
-  - `Guides <https://pillow.readthedocs.org/guides.html>`_
+  - `Handbook <https://pillow.readthedocs.org/handbook/index.html>`_
 
 - `Contribute <https://github.com/python-pillow/Pillow/blob/master/CONTRIBUTING.md>`_
 

docs/Makefile

@@ -154,3 +154,6 @@ doctest:
 
 livehtml: html
 	livereload $(BUILDDIR)/html -p 33233
+
+serve:
+	cd $(BUILDDIR)/html; python -m SimpleHTTPServer

docs/guides.rst

@@ -1,11 +0,0 @@
-Guides
-======
-
-.. toctree::
-  :maxdepth: 2
-
-  handbook/overview
-  handbook/tutorial
-  handbook/concepts
-  porting-pil-to-pillow
-  developer

docs/handbook/index.rst

@@ -0,0 +1,10 @@
+Handbook
+========
+
+.. toctree::
+  :maxdepth: 2
+
+  overview
+  tutorial
+  concepts
+  appendices

docs/index.rst

@@ -31,9 +31,8 @@ Pillow is the friendly PIL fork by `Alex Clark and Contributors <https://github.
    :maxdepth: 2
 
    installation.rst
-   guides.rst
+   handbook/index.rst
    reference/index.rst
-   handbook/appendices.rst
    releasenotes/index.rst
    about.rst
 

docs/porting-pil-to-pillow.rst

@@ -1,5 +1,7 @@
-Porting existing PIL-based code to Pillow
+Porting
-=========================================
+=======
+
+**Porting existing PIL-based code to Pillow**
 
 Pillow is a functional drop-in replacement for the Python Imaging Library. To
 run your existing PIL-compatible code with Pillow, it needs to be modified to