Update documentation

README.md

@@ -6,9 +6,15 @@ _Kotlin library to request postgres with native SQL queries_
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-* [Installation](./docs/installation.md)
-* [Migrations](./docs/migrations/migrations.md)
-* [Usage](./docs/usage/usage.md)
+---
+
+## What is this lib for?
+This library allows you to make sql requests and return the result in json format, then deserialize it into an entity.
+It also allows you to save an entity (INSERT) by serializing it and sending the json to the database, allowing you to insert several entities with their children, in a single request.
+
+It also manages the migrations of the schema of tables and stored procedures.
+
+All sql requests are handled manually for full control over what you do.
 
 ---
 
@@ -16,7 +22,16 @@ _Kotlin library to request postgres with native SQL queries_
 
 * Total control of all Postgresql features and SQL language
 * More speed and flexible than an ORM
-* [Multi level request](./docs/usage/multi-level.md)
+* [Multi level request](./docs/usage/multi-level.md) (Can return multiple tables and these children in a single request)
 * Queries are written in separate native `.sql` files
+* Unit testing of SQL queries
+* Migrations are written in separate native `.sql` files
 * Automatic tested database migration and rollback
-* Unit testing of SQL queries
+---
+## Documentation: Table of Contents
+
+* [Installation](./docs/installation.md)
+* [Migrations](./docs/migrations/migrations.md)
+* [Usage](./docs/usage/usage.md)
+* [How that works](./docs/call%20function.png) (Diagram)
+* [How to begin](./docs/checklist.md)