New: setting dependency warning messages

Resolves an issue in my todo list.

Also changed some terminology from "options" to "settings".
New: application checks for dependencies before loading

Resolves something on my todo list.
New: dropdown-options is optional

Also fixed some bugs I never realized existed in meiEditorFileUpload.js

Resolves an issue on my todo list.
Fixed: a few small bugs with icons

And a bit of CSS. Decided not to make them alternate lines as they came in; looked too weird and I couldn't get some other stuff to display properly without too much poking and prodding.