Following Stephan's fixes to spatialindex to enable
AM_MAINTAINER_MODE, the regeneration of configure
introduced a perfectly valid space in PACKAGE_STRING
which a bug in the Intel compiler results in a misparse
of, as per commit 51948d2533b43952f8916c58df2f6ca71324b8cd
from Gerard Gorman. This change reinstates Gerard's edit
of configure to fix Intel.

Since this is entirely an Intel bug and valid behaviour
on the part of autoconf, it was considered reasonable to
continue with the hack of editing configure even though
this does result in an inconsisten set of configure* files
in the spatialindex directory.