Fix comment markup

If you highlight text, then click on Italics or Bold, it works great, adding the asterisks at both ends of the highlighted text.

However, if you just click on Italics without highlighting text, it spits out two asterisks but does not move the cursor between them, which is required to actually make the text you type properly italicized.

I think it would make more sense to put the cursor in between the markup when no txt has been highlighted.