saving uncommitted changes in /etc prior to emerge run

paludis/hooks/sync_post/06-sync_overlay_cache.bash

@@ -0,0 +1,13 @@
+#!/bin/bash
+
+source "${PALUDIS_EBUILD_DIR}/echo_functions.bash"
+source "/etc/paludis/hooks/set_portdir.bash"
+
+if [[ ${TARGET} != gentoo && $(${CAVE} print-repository-metadata --raw-name format --format "%v" ${TARGET}) == e ]] ; then
+	# Number of jobs for egencache, default is number or processors.
+	egencache_jobnum="$(nproc)"
+
+	ebegin "Cache update for repository ${TARGET}"
+	egencache --jobs=${egencache_jobnum} --repo=${TARGET} --update --update-use-local-desc
+	eend $?
+fi