Allow the user to pass a parameter to define database to download (see bob.db.base#11)

gitlab/build.sh

 #!/usr/bin/env bash
-# Wed 21 Sep 2016 13:08:05 CEST
+# Tue 13 Dec 2016 17:36:51 CET
+
+# Parameters:
+#
+#   $1: database name to run the download command for. If unset, use "all"
+#
 
 source $(dirname ${0})/functions.sh
 
 run_cmd ./bin/buildout
 
+dbname=${1:-all}
+
 if [ -x ./bin/bob_dbmanage.py ]; then
-  run_cmd ./bin/bob_dbmanage.py all download --force;
+  run_cmd ./bin/bob_dbmanage.py ${dbname} download --force;
 fi
 
 if [ -d ./doc ]; then