readme for web example

examples/web/README.md

@@ -0,0 +1,18 @@
+* currently needs postgres on the default port
+* user 'postgres'
+* password 'boompje'
+* create a table
+```
+create table customers(
+    id bigint primary key, 
+    first_name varchar(50), 
+    last_name varchar(50)
+)
+```
+* insert data
+```
+insert into customers (first_name,last_name) values ('first', 'last')
+```
+* run ```cargo run -- --source examples/web --watch```
+* and head to http://localhost:3000/api/customer
+* optionally, adjust the database ddl, update the query in db.tp, and recheck the outpout