📝 Update README.

Author: momocow

README.md

@@ -19,3 +19,29 @@ addEventListener('fetch', (event) => {
 > ```toml
 > type = "webpack"
 > ``` 
+
+## Options
+- `cacheName`: string = undefined
+  > If it is `undefined`, no caches will be used. If it's `"default"`, the default cache will be used; otherwise a new cache is opened using the provided name. See [`await caches.open(name)`](https://developers.cloudflare.com/workers/runtime-apis/cache#accessing-cache).
+- `cacheTTL`: number = 300000 (in ms)
+  > The value is used to generate the max age of `Cache-Control` and compute the `Expires` time.
+- `cors`: boolean = false
+  > Allow CORS or not. If set, CORS headers will be generated and OPTIONS method will be handled.
+- `hashAlgorithm`: "sha1" | "sha256" | "sha384" | "sha512" = "sha1"
+  > Hash algorithm to use to generate ETag.
+- `leetcodeGraphqlUrl`: string = "https://leetcode.com/graphql"
+  > LeetCode GraphQL endpoint.
+- `progressType`: "global" | "session" = "global"
+  > Type of LeetCode progress to display. If it's "session", the statistics of the current active session is fetched.
+  > 
+  > This option is set for the default progress type; however, at each request, ones can provided `progress-type` parameter in the query string to change the value.
+- `userlist`: Set<string> = undefined
+  > Access control for your Worker. If provided, only usernames appear in the set is allowed to generate the progress; otherwise, 403 forbidden is responsed.
+  >  
+  > Note that leave it undefined means access control disabled, every is allowed to access the Worker.
+- `fetch`: typeof [fetch](https://developers.cloudflare.com/workers/runtime-apis/fetch) = fetch
+  > This option is passed to `graphql-request` to avoid using XMLHttpRequest (No such API in Worker Runtime).
+
+## Query String Parameters
+- `username`: string
+- `progress-type`: "global" | "session"