* typos and subbed check in spin polarized calculations for quantum espresso with a warning when computing the deltaN
* fixed typos in comments
* removed legacy mode maintaining only compatibility layer and switched to old (<3.10) python syntax
* added target density output in mu finder for brent and newton, refactored tunit test for DC, changed some comments
* moved the plovasp C++ code to c++/triqs_dft_tools/converters/vasp
* added global header triqs_dft_tools/triqs_dft_tools.hpp
* python dir based on single cmakelist file
* registered C++ tests for plovasp
* corrected imports for py3 tests for plovasp
* corrected block order in sigma_from_file and srvo3_Gloc
* exchanged ref files for sigma_from_file, srvo3_Gloc, SrVO3.ref.h5
* moved vasp converter bash scripts from dir shells to bin dir
