Add bash completion script. Fixes #154.
Add bash completion script. Fixes #154.

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