Add support for non-nixos systems

I run Debian on my Thinkpad and wanted to take advantage of nix on there
without also installing NixOS there, so here is added support for it.

users/hu/packages/zsh/config/conf.d/completions.zsh

@@ -1,9 +1,11 @@
 #!/usr/bin/env zsh
 
-if [ -z "$FZF_TAB_FILE" ] && [ ! -d "$HOME/.cache/fzf-tab" ]; then
-   echo "Installing fzf-tab"
-   git clone "https://github.com/Aloxaf/fzf-tab" "$HOME/.cache/fzf-tab"
-   FZF_TAB_FILE="$HOME/.cache/fzf-tab/fzf-tab.plugin.zsh"
+if [ -z "$FZF_TAB_FILE" ]; then
+    if [ ! -d "$HOME/.cache/fzf-tab" ]; then
+        echo "Installing fzf-tab"
+        git clone "https://github.com/Aloxaf/fzf-tab" "$HOME/.cache/fzf-tab" 
+    fi
+    FZF_TAB_FILE="$HOME/.cache/fzf-tab/fzf-tab.plugin.zsh"
 fi
 
 autoload -Uz compinit

users/hu/packages/zsh/config/conf.d/path.zsh

@@ -8,6 +8,10 @@ add_to_path() {
 
 add_to_path "$HOME/.local/bin"
 
+if [ -f "/etc/profile.d/nix.sh" ]; then
+    source /etc/profile.d/nix.sh
+fi
+
 # Language package mangers
 if [ -n "$(command -v go)" ]; then 
     export GOPATH="$HOME/.local/share/go"