Preserve exit status
Preserve exit status

Previously, webassets would always give exit status 1, which makes things that
use it think that it is failing.

aconrad/webassets,glorpen/webassets,wijerasa/webassets,heynemann/webassets,heynemann/webassets,john2x/webassets,glorpen/webassets,JDeuce/webassets,wijerasa/webassets,aconrad/webassets,aconrad/webassets,scorphus/webassets,scorphus/webassets,florianjacob/webassets,john2x/webassets,florianjacob/webassets,glorpen/webassets,heynemann/webassets,JDeuce/webassets