Expanded README

Added building instructions and example usage to README.md

README.md

@@ -1,2 +1,45 @@
 # seastar-kafka-client
 A Kafka client library for Seastar applications
+
+## Building
+To build seastar-kafka-client as a standalone library simply run the following commands:
+```bash
+$ mkdir build/release
+$ cd build/release
+$ cmake -DCMAKE_BUILD_TYPE=Release ../..
+$ make
+```
+
+Additionally, if you want to install the library, run `sudo make install`.
+
+Seastar-kafka-client uses Seastar and will try to find it installed on the machine. 
+If you wnat to provide the path manually you can set the following cmake cached variables:
+* `CMAKE_PATH_PREFIX` to `/path/to/seastar/build/release`
+* `CMAKE_MODULE_PREFIX` to `/path/to/seastar/cmake`
+
+## Usage
+Example usage of the producer client is shown in `demo/kafka_demo.cc`. Generally, it should
+look like this:
+```cpp
+#include <kafka4seastar/producer/kafka_producer>
+
+namespace k4s = kafka4seastar;
+
+# setup the producer
+k4s::producer_properties properties;
+properties.client_id = "client-id";
+
+# list of servers to establish a starting connection with
+properties.servers = {
+        {host, port} // for example {"172.13.0.1", 9092}
+};
+
+k4s::kafka_producer producer(std::move(properties));
+producer.init().wait();
+
+# scheduling the message for production
+producer.produce("topic", "key", "value");
+
+# ending work with producer
+producer.disconnect().wait();
+```