docs: adds information about config files

Author: rafaeldelboni

README.md

@@ -32,6 +32,15 @@ DB->>CI: Bulk-transact all datoms
 CI->>RE: Zip and Publish
 ```
 
+# Config `resources/config.edn`
+This file has two main functions:
+- `:db` key is defined where the datalevin files will be placed.
+- `:deps` key is defined which libraries will be downloaded, parsed and indexed in the database
+  - This configuration is made using the same [clojure.tools.deps's git coordinates](https://clojure.org/reference/deps_edn#deps_git) with some extra keys:
+    - `:project/group` use to overide the project group, currently extracted from the lib ORG 
+    - `:deps/manifest :deps` since we use tools.deps we need to set this on pure lein projects to force the download of the lib.
+    - `:project/source-paths` if a lein lib uses `:source-paths`, like reitit, we need to add this information here to indicate to clj-kondo where are the files to analyze.
+
 # Using
 Go to this github [release page](https://github.com/clj-codes/docs.extractor/releases), download and unzip the `docs-db.zip` file.