Cleanup (remove pi/ & play/ & laptop.tcl, mostly inline into virtual-programs/)

[osnr]

Mostly just so the repo is cleaner, junks unused code, colocates support code in virtual programs (display, camera, apriltag).

Please test normal functionality & calibrate & print

Can close #61 once merged (laptop simulator is finally going away)

[osnr]

Also makes ./folk.tcl executable and should fix ./folk.tcl calibrate

[cwervo]

Tested on Folk0, programs are all running fine and printing is working. When I run ./folk.tcl calibrate I'm consistently getting this though:

& I don't see the red triangles on tags so it seems like calibration fails?

[osnr]

should be fixed now -- i think stderr output from calibrate.tcl was triggering a failure of exec. also fixed realtime output

[cwervo]

Yep, calibration works well now, I think this is good to go, thanks Omar!