pick, pickmod, inhabit, inhabitmod (#921)

* the args for `pick` are now reversed as standard (old behaviour still supported to avoid breaking change)
* `pick` is also now a pattern method
* `pick` now also accepts a lookup table for pick-by-name as an alternative to pick-by-index from a list
* `inhabit` added with same behaviour as `pick`, except cycles from source patterns are squeezed into events of inhabited patterns
* Also some general doc tidying, sorry for the noise..
* There is also `pickmod` and `inhabitmod`, for wrapping indexes around rather than clamping them

packages/core/util.mjs

@@ -316,3 +316,10 @@ export function hash2code(hash) {
   return base64ToUnicode(decodeURIComponent(hash));
   //return atob(decodeURIComponent(codeParam || ''));
 }
+
+export function objectMap(obj, fn) {
+  if (Array.isArray(obj)) {
+    return obj.map(fn);
+  }
+  return Object.fromEntries(Object.entries(obj).map(([k, v], i) => [k, fn(v, k, i)]));
+}