Added NixOS and Guix support in my scripts. Updated README

zgit

@@ -1,10 +1,10 @@
-#!/bin/bash
+#!/usr/bin/env bash
 # This is just to update my git repo a tiny bit faster
 
 usage() { echo "Usage: $0 [-a \"<string>\"] [-s <file>]" 1>&2; exit 1; }
 
 while getopts "a:s:" o; do
-    case "${o}" in
+		case "${o}" in
         a)
 						a=${OPTARG}
 						git add .