added a `complex16_t` to be used with rtbf for all input data. Input
sizing is now computed uniformly using this type.

Made the output buffer in the rtbf a `void*` as part of the effort to
make more consistent the types and sizes in the input output being used.
In different modes, the output right now is always an array of floats,
but between OP_STI and OP_RAW the shape of the data is different. This
is part of perhaps using a float4 vs a complex float type like cuComplex
on the output between OP_STI and OP_RAW that a user would use to parse
data on the output.

update test scripts to use new type and make more uniform

description updates to context members, with more work still to do