Port to use SoapySDR

[xloem]

https://github.com/pothosware/SoapySDR is a single generic SDR library for a variety of devices. Using it should reduce maintenance needed for supporting new devices, simplify the plugin system, and close #8 .

[mgkuhn]

Interesting. Thanks for the link. (I would love to have something like this that also includes a driver for the National Instruments RFSA platform.)

[xloem]

Just to clarify for future visitors, SoapySDR is a general plugin API; it is not hard to add new radios. Sorry for not mentioning that earlier. GnuRadio is another alternative if people have capacity to support the gnu community.