Improve --help and --complete argument handling

libexec/tmuxifier-resolve-command-path

@@ -2,8 +2,11 @@
 set -e
 [ -n "$TMUXIFIER_DEBUG" ] && set -x
 
+# Load internal utility functions.
+source "$TMUXIFIER/lib/util.sh"
+
 # Provide tmuxifier help
-if [ "$1" == "--help" ]; then
+if calling-help "$@"; then
   echo "usage: tmuxifier resolve-command-path <command_or_alias>
 
 Outputs the absolute path to the given command or command alias."