add sphinx doc (with content taken from README). refs #92

also updated setup.py to prepare for pypi release.
minor improvemens to README and setup.py
Containerize with docker
Merge pull request #93 from scrapinghub/dockerize

Containerize with docker
maxrss can be set based on ratio of total physical mem
Merge pull request #95 from scrapinghub/percent-maxrss

support percent of total mem for maxrss check
add docs/_build to .gitignore
DOC document 'js' and 'X-Splash-js' parameters; add more links to the docs.
DOC fixed example formatting
DOC fix curl examples. See GH-72
DOC document Splash ports. See GH-26.
DOC additional references in docs
Merge branch 'master' into request-filters-and-logging

Conflicts:
	README.rst
	debian/upstart
	splash/server.py