Name: Chris Pak
SUID: 05522640
Sunet: cpak

To build this, just run ghc --make histogram.hs. For running the program, just
run the program with filenames as arguments, eg "./histogram HeartofDarkness.txt"
It is ok to use multiple files for inputs. 
If no arguments are provided, takes input from stdin, you need to end input to stdin
with EOT, or ctl-d.