refactor - introduce config folder, and other misc changes

config/slack.scad

@@ -0,0 +1,27 @@
+/*
+  Slack config to standardize different usages of slack/tolerance values.
+
+  The purpose of this config is to introduce some consistency with how slack values defined in code. E.g. Why is the
+  slack value defined as 0.3 in this file, but 0.4 in another? This will also allow model-level adjustments for tighter
+  fitting parts, for when it might not convenient to adjust the actual 3d printer (using a 3d printer at a makerspace,
+  for example).
+
+  Some important details:
+    - The general philosophy for slack applications in this project is to subtract space from sockets, while not
+      modifying the plugs. TODO: enforce this
+    - Values are signed. Positive values can be interpreted as how much to remove from the socket along some dimension.
+    - This shouldn't be used to compensate for more serious part shrinkage (> +-0.5mm differences)
+*/
+
+xySlack = 0.3;
+
+radiusXYSlack = xySlack/2;
+
+zSlack = 0.2; // TODO figure out nice default value for this. keep in mind z shrinkage
+
+overhangSlack = 0.4;
+
+supportedOverhangSlack = 0.4;
+
+// special slack cases, change if neccessary
+xBarYBarDovetailSlack = xySlack;