Update README.rst
Copy that to the first page of the document
Fix wording in simobj.rst
Fix wording in tutorial.rst
Document _cmemsubsets_

Actually it is very useful.  I should have documented it well in
the first place.
Add _cmemsubsets_ example
Add doc/source/changelog.rst
Merge branch 'improve-document'
Add gh-pages-* targets to doc/Makefile

I don't know why I had "$(BUILDDIR)/*/.*".
This is introduced in d54f43324572f63fbe090603a995bda3729dceac but
it is unclear why this was needed.
Pull only gh-pages in gh-pages-pull make target
Update link to documentation
Ignore global gitignore file in gh-pages-update
Merge branch 'move-to-gh-pages'
Update documentation front page
Update railgun/__init__.py
Bump to 0.1.7