add development environment setup script

it currently just installs the MongoDB database package
improve MongoDB installation
install Python 2.7, pip, and optionally the required modules
separate technology stack and Python modules
test bold link
improve links
add and improve links
improve links
technology stack
add docs for the setup script
install requirements with sudo
install dependencies of gevent
add license

(test the relative link)
fix relative link
Merge branch 'master' into testing