Changed . token to _dot

This change allows the dotfiles to work with chezmoi (e.g: on windows)
and improves grepability with neovim/telescope

dot_config/nushell/nu_scripts/modules/recursion/countdown.nu

@@ -0,0 +1,11 @@
+
+# Simple countdown counter from some number n to 0. Returns 0 at end
+# Designed to be used with the tramp module to avoid stack overflows via the
+# use of the Trampoline method.
+def countdown [n: int] -> int {
+  if $n == 0 {
+    0
+  } else {
+    {|| countdown ($n - 1) }
+  }
+}