version.sh: use signed (annotated) git tags

scripts/version.sh

@@ -68,8 +68,15 @@ bump_somicro() {
 }
 
 do_tag() {
+    local tag_args=""
     source "./version"
-    git tag "${VERMAJOR}.${VERMINOR}.${VERMICRO}"
+    if [ -n "${PGP_KEYID}" ]
+    then
+        tag_args="-u ${PGP_KEYID} ${tag_args}"
+    else
+        tag_args="-a"
+    fi
+    git tag ${tag_args} "${VERMAJOR}.${VERMINOR}.${VERMICRO}"
 }
 
 do_push() {
@@ -79,6 +86,8 @@ do_push() {
 
 set -ex
 
+source "${HOME}/.lwbuildrc"
+
 while [ $# -ne 0 ]
 do
     case $1 in