add parameters to allow mining other SC coins

--nfmin - default to 4
--nfmax - default to 30
--starttime - default to 1367991200
Add NFactor to the display in the hashmeter
move sc parameters to the pool structure

this should allow a failover pool that mines a different coin
Move GetNFactor into yacminer & misc cleanup

remove scrypt_test
consolidate GetNFactor into only 1 function in 1 file.
Get the NFactor based on pool values of sc_minn, sc_maxn, sc_starttime
store sc_lastnfactor with the pool and use for output

move the output of NFactor to the pool connection line
clean up variable SC implementation

use constants for MIN_NFACTOR, MAX_NFACTOR, STARTTIME
add ability to enter SC variables to a new pool through curses interface
Update documentation

give description of new parameters and details on how to use them.
Update other parts of the document to put parameters in order based on
most-critical to least-critical