Fixed parsing of the Position Append Mask field, which was read as a decimal number instead of hexadecimal. Masks containing digits A-F caused a parsing error and disconnect; masks in the range 10-99 were decoded to the wrong value, so the appended satellite, accuracy and GNSS fields were misread. Affects CV200, CV5000, GB100CG, GV30CAU, GV30CEU, GV350CEU, GV355CEU, GV50CEU, GV58CEU and GV58LAU.
