Fix --help

bin/ruby-build

@@ -118,7 +118,10 @@ usage() {
   { echo "usage: ruby-build [-v|--verbose] definition prefix"
     echo "       ruby-build --definitions"
   } >&2
-  [ -z "$1" ] && exit 1
+
+  if [ -z "$1" ]; then
+    exit 1
+  fi
 }
 
 list_definitions() {
@@ -137,8 +140,6 @@ case "$1" in
 "-h" | "--help" )
   usage without_exiting
   { echo
-    echo "Options:"
-    echo
     echo "  -v/--verbose     Verbose mode: print compilation status to stdout"
     echo "  --definitions    List all built-in definitions"
     echo