removed dependency to Xonsh for Validation LFR Filters

Some more cleaning Factorised LFR filters testbench for all test cases.

Make vsim target now works on windows.

Fixed Makefile. Now correctly forward targets to subfolders

Removed unmaintained C drivers. Removed insanely dangerous bash scripts. Moved some Test from design folder to tests folder. Updated readme. Updated top Makefile.

Moved sig_reader to lpp.lpp_sim_pkg.

Improved testbench for LFR's F0 IIR Filter, now processed input is read from a file.

Added file init for RAM_CEL IP.[Need tests] Made IIR filter design more GHDL friendly.

Exposed tech parameter from filters to top lpp_lfr_filter. Added testbench design for f0 lfr filter.

Added missing files (sdc/pdc/makefile) for LFR-EQM boards Improved Validation IIR LFR design Update LFR Filter, first implementation of filter RAM Init.