Demo update 0.2.4

HiHere is what's new in the latest update: better info on placing buildings, a clearer statement on how long the demo runs, and a challenge for the veterans who reach tier 2.

Demo update 0.2.4

• New optional challenge once your T2 chain is running: Errol dares you to beat your uncles record, a 250 oz cleanup.

• The demo's three seasons are now stated up front, and a season counter sits in the top bar.

• Rotating a building with R is finally explained: on the placement banner, by Errol, and in the controls list.

• Controls list updated with every way to mark and unmark dirt cells, and controls for placement.

• Fixed the timing of the "hire more diggers" tip, it used to arrive when you already hired the months diggers.

Thanks for playing and reporting any bugs./ Sebastian