I propose to support choosing a location for the SAGE_LOCAL tree, using

./configure --prefix=SAGE_LOCAL

(the default would be, as before, the local subdirectory of SAGE_ROOT - see patch on the ticket).

I am fully aware that Sage's build system does not have a separation between 'make' and 'make install'; see #21495 for that.

Nevertheless, SAGE_LOCAL should be considered the same as the prefix in the sense of the autotools.

This ticket is a step towards #21566.

Release manager configure tarball: http://sage.ugent.be/www/jdemeyer/sage/configure-214.tar.gz

CC: @jdemeyer @embray @kiwifb @nexttime @dimpase

Component: build

Author: Matthias Koeppe, Jeroen Demeyer

Branch: e5926b1

Reviewer: Jeroen Demeyer, Erik Bray, Matthias Koeppe

Issue created by migration from https://trac.sagemath.org/ticket/21479