Bridge bidding flowcharts: Introduction

This begins a series of flowcharts detailing bridge bidding in the Standard American Bidding convention. The exact details are from http://www.math.cornell.edu/~belk/bridge.htm

I am a complete bridge novice so this exercise served two functions:
1. It forced me to think through the conventions, helping commit them to memory.
2. This was an opportunity to learn how to use TikZ in LaTeX.

I make no claims about accuracy of these charts or efficacy of the strategy they show.