Improve ac_converter to print a help message.
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QuLogic/meson,fmuellner/meson,QuLogic/meson,pexip/meson,pexip/meson,ernestask/meson,becm/meson,mesonbuild/meson,pexip/meson,ernestask/meson,trhd/meson,becm/meson,jeandet/meson,mesonbuild/meson,jeandet/meson,becm/meson,pexip/meson,jeandet/meson,becm/meson,ernestask/meson,ernestask/meson,fmuellner/meson,MathieuDuponchelle/meson,jpakkane/meson,mesonbuild/meson,QuLogic/meson,jpakkane/meson,pexip/meson,QuLogic/meson,fmuellner/meson,pexip/meson,pexip/meson,thiblahute/meson,ernestask/meson,jpakkane/meson,fmuellner/meson,becm/meson,jpakkane/meson,QuLogic/meson,fmuellner/meson,MathieuDuponchelle/meson,trhd/meson,trhd/meson,mesonbuild/meson,jeandet/meson,trhd/meson,mesonbuild/meson,jpakkane/meson,becm/meson,becm/meson,ernestask/meson,jpakkane/meson,MathieuDuponchelle/meson,mesonbuild/meson,ernestask/meson,becm/meson,becm/meson,jeandet/meson,QuLogic/meson,mesonbuild/meson,QuLogic/meson,fmuellner/meson,ernestask/meson,thiblahute/meson,ernestask/meson,jpakkane/meson,mesonbuild/meson,fmuellner/meson,becm/meson,jeandet/meson,trhd/meson,MathieuDuponchelle/meson,thiblahute/meson,thiblahute/meson,jpakkane/meson,jpakkane/meson,pexip/meson,fmuellner/meson,trhd/meson,thiblahute/meson,MathieuDuponchelle/meson,thiblahute/meson,pexip/meson,jeandet/meson,trhd/meson,MathieuDuponchelle/meson,jeandet/meson,QuLogic/meson,thiblahute/meson,MathieuDuponchelle/meson,fmuellner/meson,trhd/meson,mesonbuild/meson,thiblahute/meson,thiblahute/meson,QuLogic/meson,jeandet/meson,MathieuDuponchelle/meson,MathieuDuponchelle/meson,trhd/meson,mesonbuild/meson,pexip/meson