Minor issue: Undefined index error in update-last-modified.php on line 243

Hi @djuric,

This is a very minor issue that does not affect the plugin’s functionality at all.

I have debug mode enabled. In WP backend, when creating new post/page, until it is saved for the very first time (as draft or published) I get an ugly error message:

Notice: Undefined index: stopmodifiedupdate in …/wp-content/plugins/change-last-modified-date/update-last-modified.php on line 243

I am sure this can be easily prevented.

Thanks again for this great plugin!