C-band goes dual channel

Small update for C-band users to allow simultaneous demodulation of 2 channels at the same time. Also now built for 64 bit to help ease CPU usage a bit.

NB: if you are upgrading from the 32 to 64 bit version uninstall the 32 bit version first.

New:
Dual 10.5kbps C-band demodulation by using stereo input.
64bit build

Changes:
Time check for SBS1 packets
Concatenated SBS1 packets
Added timestamp to SBS1 packets