The git spkg fails to build if gettext is not installed, see https://groups.google.com/d/msg/sage-devel/RAWInaDhz5c/lQYXrKQ4aXEJ
We should try again without gettext if necessary.
Also, clean up spkg-install/spkg-check.
Component: build
Author: Volker Braun
Branch/Commit: u/vbraun/git_without_gettext @ 16d8bba
Reviewer: R. Andrew Ohana
Issue created by migration from https://trac.sagemath.org/ticket/15401