feat: add stopwatch

bin/stopwatch

@@ -0,0 +1,20 @@
+#!/bin/sh
+
+stopwatch() {
+    local BEGIN=$(date +%s)
+    echo Starting Stopwatch...
+
+    while true; do
+        local NOW=$(date +%s)
+        local DIFF=$(($NOW - $BEGIN))
+        local MINS=$(($DIFF / 60))
+        local SECS=$(($DIFF % 60))
+        local HOURS=$(($DIFF / 3600))
+        local DAYS=$(($DIFF / 86400))
+
+        printf "\r%3d Days, %02d:%02d:%02d" $DAYS $HOURS $MINS $SECS
+        sleep 0.5
+    done
+}
+
+stopwatch