Move glass appearance into reagent datums

~~GitHub's not working right, it's not checking mergeability, just getting stuck on "checking mergeability". I'm gonna make this anyway - it's 1 ahead, 0 behind dev, so it *should* merge alright.~~
Seems it's fixed itself when I made the PR.

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As in title.
I've adjusted the names a bit so that most are "glass of [contents]", which stops them showing up as "This is Beer glass", changing it to "This is a glass of beer".
Exceptions to the "glass of [contents]" adjustment:
* Beepsky Smash, since it's not in a glass. \improper doesn't work, unfortunately, so it'll show as "This is Beepsky Smash".
* Grape soda, since the sprite is a can ("can of grape soda")

Also fixes a few "glass of... what?" instances where the reagent in the glass was something relatively sensible to put in a glass (hot chocolate, tea) - medicines, toxins and other things-that-should-not-be-in-glasses will still show up as "glass of... what?" unless they had other names/descriptions set already (blood, welding fuel).

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This will conflict with #6961 at merge-time (`drinkingglass.dm`); simply ignore the change made by that PR.