make swirl play nice with testit function from swirlify
from and to feature prototyped for test mode
complete first part of lesson when starting partway thru in test mode
fix testit() no args situation
check that 'to' is greater than 'from' in test mode
fix bug related to lesson cutoff
remove extraneous code
Merge pull request #170 from swirldev/fromto

Extend 'test' mode functionality to accommodate new swirlify features