Do not assume that build-docker.sh is run from the repository root directory

build-docker.sh

@@ -1,4 +1,5 @@
 #!/bin/bash -e
+DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
 
 BUILD_OPTS="$*"
 
@@ -61,7 +62,7 @@ if [ "${CONTAINER_EXISTS}" != "" ] && [ "${CONTINUE}" != "1" ]; then
 	exit 1
 fi
 
-${DOCKER} build -t pi-gen .
+${DOCKER} build -t pi-gen "${DIR}"
 if [ "${CONTAINER_EXISTS}" != "" ]; then
 	trap 'echo "got CTRL+C... please wait 5s" && ${DOCKER} stop -t 5 ${CONTAINER_NAME}_cont' SIGINT SIGTERM
 	time ${DOCKER} run --rm --privileged \