Abbreviations

Often used abbreviations and shortenings
 * PTS - Protoshares
 * XPM - Primecoins
 * Val/h - Value per hour
 * ch - chain
 * ch/h - chains per hour
 * PPS - primes per second
 * SPS - seives per second
 * NPS - numbers per second
 * ACC = average canidate count
 * col/m - collisions per minute