[hpsdr] Orion_v5.2 firmware release for Orion MkI/ANAN-200D

[Joe Martin]

All, 

Orion_v5.2 firmware is available for download on the GitHub repository:

https://github.com/TAPR/OpenHPSDR-Firmware/tree/master/Protocol%201/Orion%20(ANAN-200D)

This firmware version simplifies Rx5 frequency switching to improvePureSignal mode performance with respect to board-to-board timing differences that may exist between different ANAN-200D radios.  

I thank Joe K2GX and John W1QS for kindly helping me test the firmware.  

73, Joe K5SO