Add build settings to "dub describe" output.
Add build settings to "dub describe" output.

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