Added a "search" algorithm but I didn't really know where to put it, so I put it here.

Essentially it takes an input string (say something like "calculus textbook book") and it does the following:

* grabs all sales
* creates an array of weights and an array of indexes
* splits the input string into separate words delimited by " "
* Iterates over every description and every word and increments the weight of that description if the word is present
* Sorts the weight array to descending order
* Simultaneously swaps the values in the index/enumeration array corresponding to the weight sort
* iterates over the index/enumeration array and inserts that sale into the table

I'm not very good at javascript, so if someone can make it better so it doesn't have to query the database every time, that'd be great.