epm: inform about missed epm-play package

bin/epm

@@ -54,7 +54,11 @@ load_helper()
 
     local CMD="$SHAREDIR/$1"
     # do not use fatal() here, it can be initial state
-    [ -r "$CMD" ] || { message 'FATAL: Have no $CMD helper file' ; exit 1; }
+    if [ ! -r "$CMD" ] ; then
+        message 'FATAL: Have no $CMD helper file'
+        [ "$1" = "epm-play" ] && message 'Install eepm-play package to use epm play command.'
+        exit 1
+    fi
     eval "$shieldname=1"
     # shellcheck disable=SC1090
     . $CMD