fix typos, add styles, edit tools page markup

I'm having trouble making these separate PRs so one will have to suffice.

* Couple of typos fixed... no story there.
* Affiliates Overview page has widgets that are typically draggable. It doesn't look like that'll be part of AWP so I replaced the "cursor: move;" default WP style for the widget titles because the cursor was misleading. `#affwp-dashboard-widgets-wrap .postbox h3` was great for that.
* However, the same situation was true for the widgets on the tools pages... misleading cursors. The only issue here is that the widgets weren't wrapped in an AWP-specific container like the Overview widgets. So I made one `#affwp-tools-widgets-wrap` and added it to the CSS selector from above. Adding that container around each tab's widgets caused for more lines "edited" than I intended so don't be misled there. It's just indentations. I also added HTML comments for the new container as well as the missing `.metabox-holder` comments.

Let me know if you do intend to make those widgets draggable. If not, this'll take care of it. Also let me know if I missed any of these .postbox widgets. I think I found them all.