Add vibe-d as an optional dependency to let vibe.d compatibility code also work for separate compilation of packages.
Add vibe-d as an optional dependency to let vibe.d compatibility code also work for separate compilation of packages.

rjframe/dub,D-Programming-Language/dub,schuetzm/dub,Abscissa/dub,Flamaros/dub,dreamsxin/dub,grogancolin/dub,alexeibs/dub,xentec/dub,p0nce/dub,Geod24/dub,jelmansouri/dub,gedaiu/dub,nazriel/dub,Abscissa/dub-data-mod,y12uc231/dub,jeanbaptistelab/dub