Change current algo detection method

nfactor sgminer doesn't provide a simple way to distinguish between
nfactor 10 and 11 from the API.
Consequently, instead of using the cgminer API to detect the current
runnning algo, use a variable to keep track of the last script ran.

It should solve most of #1
Update README and add SMOS sample scripts

SMOS scripts courtesy of Strider3000