Add new lib for shell

shellib/dot-local/lib/shellib/libseb.sh

@@ -0,0 +1,12 @@
+log() {
+  # Write msg to stderr.
+  # Taken from https://github.com/oils-for-unix/oils/blob/master/stdlib/osh/two.sh
+  echo "$@" >&2
+}
+
+die() {
+  # Write error msg with script name and exit with status 1.
+  # Taken from https://github.com/oils-for-unix/oils/blob/master/stdlib/osh/two.sh
+  log "$@: fatal $@"
+  exit 1
+}