Merge pull request #1 from Pennham/penn-dev

Penn dev
Merge pull request #3 from Pennham/penn-dev

Penn dev
Merge pull request #5 from Pennham/penn-dev

Unit tests added
using timer object to measure runtime
some changes in inheritance for SortLists
use new ListFromFile class to get PiList
Merge branch 'penn-dev' into doc
changed inheritance for Sorters