implement add and edit

We now have working pages to add recipes and edit recipes! These are
not styled and not ajaxy, but they are fully functional. They use
WTForms, so we can add validators and such without too much trouble,
although not much is in place yet.
updated setup.py

Added WTForms and flask-wtf to install_requires. Bumped version to 0.2
because I changed the model.
add an edit button to recipe view page

Also change index to show a list of links to recipes for now.