Update README and doccomments

Signed-off-by: trivernis <trivernis@protonmail.com>

README.md

@@ -6,8 +6,9 @@ The official API documentation can be found [here](https://hydrusnetwork.github.
 ## Example
 
 ```rust
-
-use hydrus_api_rs::Client;
+use hydrus_api::Client;
+use hydrus_api::paths::adding_tags::{AddTagsRequestBuilder, TagAction};
+use std::env;
 
 #[tokio::main]
 async fn main() {

src/lib.rs

@@ -1,3 +1,36 @@
+//! ## About
+//! This crate provides a rust wrapper for the hydrus client API. All request require an access
+//! token that can be retrieved in the hydrus client from the *review services* dialog.
+//! Different actions require different permissions, you can read about it in the [official docs](https://hydrusnetwork.github.io/hydrus/help/client_api.html).
+//!
+//! ## Usage Example
+//! ```
+//! use hydrus_api::Client;
+//! use hydrus_api::paths::adding_tags::{AddTagsRequestBuilder, TagAction};
+//! use std::env;
+//! # #[tokio::test]
+//! # async fn doctest() {
+//!
+//! Client::new(
+//!     env::var("HYDRUS_URL").unwrap(),
+//!     env::var("HYDRUS_ACCESS_KEY").unwrap(),
+//! ).unwrap();
+//! // let's first import a file
+//! let hash = client.add_file("/path/to/my/file").await.unwrap().hash;
+//!
+//! // and now let's add tags to it
+//! let request = AddTagsRequestBuilder::default()
+//!     .add_hash(hash)
+//!     // for each tag the service has to be specified
+//!     .add_tags("my tags", vec!["beach".into(), "summer".into()])
+//!     // with tag actions tags can also be removed. It's especially useful for the PTR
+//!     .add_tag_with_action("my tags", "rain", TagAction::DeleteFromLocalService)
+//!     .build();
+//!
+//! client.add_tags(request).await.unwrap();
+//! # }
+//! ```
+
 #[macro_use]
 extern crate serde_derive;