view_sample_scatterplot.html:
- fixed bug where selection was only working in the selected cell, not in any other cells

models.py:
- in Sample model, make sure the fcs data is sorted by parameter number to ensure the header matches the column data
- using numpy method to add a new column for category...still need to figure our how to efficiently make this column data strings instead of numbers, but maybe we'll use codes for the categories
- limiting the number of fcs data points to 100 to make the browser less laggy when making selections