Use `python3` explicitly

On a lot of systems `python` will refer to a parallel Python 2
installation so `python3` should be used when not working in a
virtual environment.
Split up description on how to open the Python console
Merge pull request #24 from maciejgryka/master

Added more Windows-specific PostgreSQL installations steps
Fixed conflict
Merge branch 'foonicorn-master'
Update README.md

Made very minor modifications to wording for correct English usage.  One typo in the reference to "...settings.py" corrected.
Update README.md

Very minor changes to wording after proofreading.  "Go to Post..." changed to "Go to Posts..." for consistency with the image that it refers to (although of course the model itself is named "Post", but it appears in the admin page as "Posts")
first changes
added 'elements' to the text
Changed the psycopg2 install method for Windows.

The current suggested method relies on git being installed
on the user's machine.
This new one is slightly more complex (there's an
extra step of downloading a prebuilt binary) but
it should work with nothing else installed.
Minor wording changes after proofreading
Minor wording changes after proofreading
split up Windows install instructions for psycopg2 and added Heroku Toolbelt install
added installation of Heroku Toolbelt during setup to allow pip-installing using Git for psycopg2 on Windows; I've kept the Toolbelt section in the deployment chapter too for people who have already gone through the setup
Merge pull request #29 from rebkwok/master

Proofreading changes
Merge pull request #27 from evildmp/html-chapter

Suggested changes for HTML chapter
Explain how to add Postgres to PATH on OS X
All codes are working.

* cleanup in codes

* some explanations and hints for some troubleshooting
Removed redundant info about installing psycopg2
Some more native speaker proofreading

Gave the 'database', 'code editor', 'Django installation' and 'Start a Django Project' pages a quick linguistic overhaul.