Add Tomato Relish recipe

This came from Claire, and is supposedly the recipe her grandmother
uses.

Signed-off-by: Anna Schumaker <Anna@OcarinaProject.net>

sauces/tomato_relish.tex

@@ -0,0 +1,35 @@
+%
+% Copyright 2016 (c) Anna Schumaker.
+%
+\documentclass{../recipe}
+
+\recipeName{Tomato Relish}
+\recipeMakes{9 cups}{relish}
+
+\begin{document}
+\begin{ingredients}
+\addIngredient{4\half pounds}{tomatoes, chopped}
+\addIngredient{3 medium}{onions, peeled and chopped}
+\addIngredient{3\quarter cups}{vinegar, divided}
+\addIngredient{2 cups}{sugar}
+\addIngredient{2 tablespoons}{salt}
+\addIngredient{3 teaspoons}{mustard powder}
+\addIngredient{3 teaspoons}{curry powder}
+\addIngredient{1 tablespoon}{cornflour}
+\end{ingredients}
+
+\begin{steps}
+\addStep{Combine \ingredient{tomatoes}, \ingredient{onions},
+	 \textbf{3 cups} \ingredient{vinegar}, \ingredient{sugar},
+	 \ingredient{salt}, \ingredient{mustard powder}, and
+	 \ingredient{curry powder}, in a large saucepan.  Bring to a boil,
+	 stirring constantly.}
+\addStep{Boil for \textbf{1\half hours} stirring occasionally.}
+\addStep{Mix \ingredient{cornflour} and \textbf{\quarter cup}
+	 \ingredient{vinegar} into a paste.  Add to \ingredient{tomatoes},
+	 stirring until thickened.}
+\addStep{Pour into sterilized jars and seal immediately.}
+\end{steps}
+
+\addSuggestion{Vinegar}{Try using cider vineger for a tangier taste.}
+\end{document}