[BUILD] fix snapshot date extraction with negative timezones
Building with a last commit having a negative time offset would make
"date" complain.
diff --git a/Makefile b/Makefile
index 89f1b61..2619a65 100644
--- a/Makefile
+++ b/Makefile
@@ -259,7 +259,7 @@
ifneq ($(VERSION),)
# OK git is there and works.
SUBVERS := $(shell comms=`git-log --no-merges v$(VERSION).. 2>/dev/null |grep -c ^commit `; [ $$comms -gt 0 ] && echo "-$$comms" )
-VERDATE := $(shell date +%Y/%m/%d -d "`git-log HEAD^.. 2>/dev/null | grep -m 1 ^Date: | cut -f2- -d: | cut -f1 -d+`" )
+VERDATE := $(shell date +%Y/%m/%d -d "`git-log HEAD^.. 2>/dev/null | sed -ne '/^Date:/{s/\(^[^ ]*:\)\|\( [-+].*\)//gp;q}'`" )
endif
endif