re-defining complex data type macro as struct
re-defining complex data type macro as struct

 * improves reliability for C++ build systems
 * configure scripts with AC_LANG_PUSH([C++]) defined
 * allows functions to return object (no longer array)
 * moot for internal processing which uses the standard C 'float
   complex' type

cjcliffe/liquid-dsp,andrepuschmann/liquid-dsp,wangning223/liquid-dsp,manuts/liquid-dsp,biotrump/liquid-dsp,JayKickliter/liquid-dsp,andrepuschmann/liquid-dsp,cjcliffe/liquid-dsp,andrepuschmann/liquid-dsp,manuts/liquid-dsp,cjcliffe/liquid-dsp,manuts/liquid-dsp,cjcliffe/liquid-dsp,biotrump/liquid-dsp,jgaeddert/liquid-dsp,wangning223/liquid-dsp,manuts/liquid-dsp,andrepuschmann/liquid-dsp,wangning223/liquid-dsp,biotrump/liquid-dsp,jgaeddert/liquid-dsp,JayKickliter/liquid-dsp,wangning223/liquid-dsp,andrepuschmann/liquid-dsp,jgaeddert/liquid-dsp,JayKickliter/liquid-dsp,biotrump/liquid-dsp,biotrump/liquid-dsp,JayKickliter/liquid-dsp,wangning223/liquid-dsp,JayKickliter/liquid-dsp,jgaeddert/liquid-dsp,cjcliffe/liquid-dsp,manuts/liquid-dsp,jgaeddert/liquid-dsp