Update README with better example usage

README.md

@@ -10,7 +10,11 @@ A very basic POSTGREST client and utils
 
 ```python
 from postgrestutils.client import pgrest_client
-pgrest_client.get("kerbals?select=id,forename")
+
+payload = {
+    "select": "id,forename"
+}
+pgrest_client.get("kerbals", params=payload)
 ```
 
 ##### Other projects
@@ -23,7 +27,10 @@ settings.JWT = ""
 
 from postgrestutils.client import pgrest_client
 
-res = pgrest_client.get("kerbals?select=id,forename")
+payload = {
+    "select": "id,forename"
+}
+res = pgrest_client.get("kerbals", params=payload)
 ```
 
 #### Django helpers