docs: update README to include Contact Exports API section and example

Author: narekhovhannisyan

README.md

@@ -33,6 +33,7 @@ Currently, with this SDK you can:
   - Contacts CRUD
   - Lists CRUD
   - Contact Fields CRUD
+  - Contact Exports
 - General
   - Templates CRUD
   - Suppressions management (find and delete)
@@ -126,6 +127,10 @@ Refer to the [`examples`](examples) folder for the source code of this and other
 
 - [Contact Fields](examples/contact-fields/everything.ts)
 
+### Contact Exports API
+
+- [Contact Exports](examples/contact-exports/everything.ts)
+
 ### Sending API
 
 - [Advanced](examples/sending/everything.ts)