Added remez_fir class + test_remez.cpp for Remez FIR filter design. Added mlsd class, and dvb_conv_encoder - Convolution encoder for rate 1/2 DVB generators. Modified qpsk_ber_test, cmplx_allpass_halfband, cmplx.h, and makefile for qpsk and qpsk_vr, to compile without errors under g++ and visual c++.