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/sourced/filesystem/up.nu

@@ -0,0 +1,8 @@
+use std repeat;
+
+# Go up a number of directories
+def --env up [
+    limit = 1: int # The number of directories to go up (default is 1)
+  ] {
+    cd ("." | repeat ($limit + 1) | str join)
+}