Unstable Update 8.17.19

In this update…

* Gold ore blocks now produce gold ore, which must be smelted.
* Gold blocks join copper and iron blocks.
* New biome – wetlands. Occurs where land is relatively low and wet.
* New plant – bamboo. Grows in wetlands.
* Employee info screen is now tabbed and includes some additional info.
* Backpack isn’t a separate dialog, and shows icons.
* Digging now requires dwarves to equip picks. Miners come with a pick already so you won’t notice – but this is the first step toward equipable items.
* Why not make tables and chairs out of peppermint??
* Kill things on the debug menu now uses the selection buffer so it will be more useful if you’ve got a pest problem.
* Sliders on options screen show a value (where it makes sense)
* Added confusing slider for species limit – 100% means 100% of the default limit of 15.
* Building floor will now queue up a dig task first.
* Fixed bug that let creatures spawn without beyond species limit.
* Fixed bug that made craft icons vanish.
* Added hotkey (esc) that closes popups.