Added multi-API-key support and API rate-limiting.

.env.example

@@ -33,3 +33,13 @@ API_KEY=""
 # This is the name that will be pre-filled when you go to upload custom files for a modpack.
 # Unset behaviour: You will need to specify the author every time.
 AUTHOR_NAME="John Doe"
+
+# (Optional) API Rate-limit Requests
+# The number of requests that can be made to the API by one IP address within the set window before it will block them.
+# Default: 1000
+API_RATE_REQUESTS=1000
+
+# (Optional) API Rate-limit Window
+# The amount of time (in milliseconds) that the request limit is applied to.
+# Default: 60000
+API_RATE_WINDOW=60000