Add/improve texts that describe items embedded in tiles

[Mikolaj]

These are the idesc fields in this file: https://github.com/LambdaHack/LambdaHack/blob/master/GameDefinition/Content/ItemKindEmbed.hs#L42

The descriptions are expected to be rather concise and, more or less, justify or colour the effects of the item. Usually, let's try to avoid second or first person ("you", "we") and let's limit that to backstory or plot texts, e.g., scenario texts. The descriptions should rather add to the mood, entertain, surprise the player, than move the plot forward or explain things in a boring, exhaustive way. Thus, by their brevity and quirkiness they build a counterbalance to the game texts that must be long and exhaustive, if only to help new players (especially those new to roguelikes) not feel lost.

Only items embedded in rare tiles can have longer descriptions and these can build up the backstory, give gameplay hints, etc. Examples of such rare tiles are those that somehow define the room they appear in (see #126), e.g., a kitchen sink in a kitchen. Such texts should definitely describe the room, not just the tile, and do that in the context of the gameplay/backstory/plot/mood. Some remarks about the theme and mood of LambdaHack the game are here (but mostly just look at the other content; playing the game a bit doesn't hurt either): https://github.com/LambdaHack/LambdaHack/wiki/Sample-dungeon-crawler

The descriptions are visible whenever the aiming crosshair is over a tile that has an embedded item. Also, they can be browsed in one of the item lore menus accessible from the dashboard. To see (most probably) all embedded item descriptions that can be generated in a game, run make see-caves (or the corresponding commandline copied from the Makefile, if you don't have make).

If the description you have come up with requires some changes to the stats/effects of the embedded item, please feel free to suggest those, even in vague terms. Also, feel free to split embedded items for literary reasons alone, even if they should differ only by description and perhaps the symbol and its colour. The same about adding new ones.

The texts are assumed to be licensed by their authors under BSD3. This should spare all of us us any legal headaches when moving and matching content bits between various free software games based on LambdaHack.