New price model added

Number of price models availiable increased - CPA price model was added to the list. Network operator may set this model for his network by going to "Edit" menu and choosing bookmark named "Main settings". There operator may provide an abbreviation for the model (like CPL - Cost per Lead ) and an external name ("Lead"), set price ( in $, $V). Also, operator may add a commentary explaining the nature of actions which fall under this price model.