Added ModifyValues to Qsl_Rcvd, Eqsl_Qsl_Rcvd, and Lotw_Qsl_Rcvd
classes to replace V status with Credit_Granted values of
DXCC:xxx, DXCC_MODE:xxx, and DXCC_BAND_xxx where xxx is
CARD, EQSL, or LOTW as appropriate.
Modified user manual to include these modifications.
This completes changes for issue #32.