Update samples for windowing and main class detection (#79)

- update README instructions

- remove windowing from wordcount sample

- rely on main class detection in SCFn in uppercase sample

Author: trisberg

samples/uppercase/README.adoc

@@ -26,7 +26,7 @@ N.B. this sample uses Spring (without really needing to, but just to show how it
 === create the function and its input topic
 
 ```
-riff create java --handler 'uppercase&main=functions.UppercaseApplication'
+riff create java --handler uppercase
 ```
 
 === publish a message and wait for a reply

samples/wordcount/README.adoc

@@ -22,10 +22,36 @@
 ./mvnw clean package
 ```
 
-=== create the function and its input topic
+=== create the function and its input topic resource definitions
 
 ```
-riff create java --input words --output counts --handler functions.Wordcount
+riff init java --input words --output counts --handler functions.Wordcount
+```
+
+=== modify the function resource definition's windowing declaration
+
+Modify the `wordcount-function.yaml` that was just created. Change the `windowing`
+declaration to be either 
+
+- time based:
++
+```
+  windowing:
+    time: 10s
+```
+
+- or, based on number of messages:
++
+```
+  windowing:
+    size: 5
+```
+
+=== build and create the function and its input topic
+
+```
+riff build
+riff apply
 ```
 
 === publish messages and witness grouped counts
@@ -40,13 +66,26 @@ In a different terminal window, in quick succession:
 riff publish --input words --data Two
 riff publish --input words --data One
 riff publish --input words --data Two
+riff publish --input words --data Three
+riff publish --input words --data One
+riff publish --input words --data Two
 ```
 
 You'll see output similar to the following:
+
 ```
- Content-Type["text/plain"]	timestamp["1519342606257"]{"one":1,"two":2}
+ timestamp["1527008218465"]{"One":2,"Two":2,"Three":1}
+ timestamp["1527008230607"]{"Two":1}
 ```
 
+or 
+
+```
+ timestamp["1527008390450"]{"One":2,"Two":3,"Three":1}
+```
+
+depending on how you configure your windows.
+
 === delete the function and its input topic
 
 ```

samples/wordcount/src/main/java/functions/Wordcount.java

@@ -1,6 +1,5 @@
 package functions;
 
-import java.time.Duration;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.function.Function;
@@ -11,8 +10,7 @@ public class Wordcount implements Function<Flux<String>, Flux<Map<String, Intege
 
 	@Override
 	public Flux<Map<String, Integer>> apply(Flux<String> words) {
-		return words.window(Duration.ofSeconds(10))
-				.flatMap(w -> w.collect(HashMap::new, (map, word) ->
-						map.merge(word, 1, Integer::sum)));
+		return Flux.from(words.collect(
+				HashMap::new, (map, word) -> map.merge(word, 1, Integer::sum)));
 	}
 }