Documentation Update

This is a huge PR, sorry.

We have the following:
- Added example document generator that is called by `make html` (updated Makefile and make.bat).
- Added tutorial documentation adapted from enaml 0.6.8 and associated new images.
- Updated `docs/source/example/index.rst`.
- Added `<< autodoc-me >>` pragma to example files.
- Put a link to the Enaml Google Group in FAQ, and an "Under Construction" notice in the Arch Ref.
- Fixed some docstrings that were throwing Sphinx build errors and warnings.
- Copied the static images from `examples/widgets/images` to `docs/source/examples/images`.

The generated example files have a link to the raw enaml file, the docstring, the image, and a literal include of the raw enaml file.  I flagged all of the examples (other than the tutorials) for autodoc, to at least get the base documentation in there.   The behavior you should see during the build is a window pop up, move to the upper left corner, then disappear, and the next one appear after it.  I tried running with PySide, but the Live Editor threw an error, so I added a forced QT_API=pyqt.

An enhancement would be to expand on the `<< autodoc-me >>` pragma to include other directives, like taking a second snapshot with a window expansion, to show the constraint behavior.