Convert envProps to loading all props from properties file

**Summary**
Allow KTs to be more portable between Docker and non-Docker environments:

e.g. convert this line

```
props.put(StreamsConfig.BOOTSTRAP_SERVERS_CONFIG, envProps.getProperty("bootstrap.servers"));
```

to below (no explicit setting of `BOOTSTRAP_SERVERS_CONFIG` is required)

```
final Properties props = KafkaProducerApplication.loadProperties(args[0]);
```

**Target KTs to change**

```
grep -ir put * | grep -i getProperty | grep -v input | awk -F: '{print $1;}' | uniq
```

aggregating-average/kstreams/code/src/main/java/io/confluent/developer/RunningAverage.java
aggregating-count/kstreams/code/src/test/java/io/confluent/developer/AggregatingCountTest.java
aggregating-count/kstreams/code/src/main/java/io/confluent/developer/AggregatingCount.java
aggregating-minmax/kstreams/code/src/test/java/io/confluent/developer/AggregatingMinMaxTest.java
aggregating-minmax/kstreams/code/src/main/java/io/confluent/developer/AggregatingMinMax.java
aggregating-sum/kstreams/code/src/test/java/io/confluent/developer/AggregatingSumTest.java
aggregating-sum/kstreams/code/src/main/java/io/confluent/developer/AggregatingSum.java
cogrouping-streams/kstreams/code/src/test/java/io/confluent/developer/CogroupingStreamsTest.java
cogrouping-streams/kstreams/code/src/main/java/io/confluent/developer/CogroupingStreams.java
connect-add-key-to-source/kstreams/code/src/test/java/io/confluent/developer/connect/jdbc/specificavro/StreamsIngestTest.java
connect-add-key-to-source/kstreams/code/src/main/java/io/confluent/developer/connect/jdbc/specificavro/StreamsIngest.java
dynamic-output-topic/kstreams/code/src/test/java/io/confluent/developer/DynamicOutputTopicTest.java
dynamic-output-topic/kstreams/code/src/main/java/io/confluent/developer/DynamicOutputTopic.java
filtering/kstreams/code/src/test/java/io/confluent/developer/FilterEventsTest.java
filtering/kstreams/code/src/main/java/io/confluent/developer/FilterEvents.java
finding-distinct/kstreams/code/src/test/java/io/confluent/developer/FindDistinctEventsTest.java
finding-distinct/kstreams/code/src/main/java/io/confluent/developer/FindDistinctEvents.java
fk-joins/kstreams/code/src/test/java/io/confluent/developer/FkJoinTableToTableTest.java
fk-joins/kstreams/code/src/main/java/io/confluent/developer/FkJoinTableToTable.java
joining-stream-table/kstreams/code/src/test/java/io/confluent/developer/JoinStreamToTableTest.java
joining-stream-table/kstreams/code/src/main/java/io/confluent/developer/JoinStreamToTable.java
kafka-producer-application/kafka/code/src/test/java/io/confluent/developer/KafkaProducerApplicationTest.java
kafka-producer-application/kafka/code/src/main/java/io/confluent/developer/KafkaProducerApplication.java
kafka-producer-application-callback/kafka/code/src/test/java/io/confluent/developer/KafkaProducerCallbackApplicationTest.java
kafka-producer-application-callback/kafka/code/src/main/java/io/confluent/developer/KafkaProducerCallbackApplication.java
kafka-streams-schedule-operations/kstreams/code/src/test/java/io/confluent/developer/KafkaStreamsPunctuationTest.java
kafka-streams-schedule-operations/kstreams/code/src/main/java/io/confluent/developer/KafkaStreamsPunctuation.java
merging/kstreams/code/src/test/java/io/confluent/developer/MergeStreamsTest.java
merging/kstreams/code/src/main/java/io/confluent/developer/MergeStreams.java
message-ordering/kafka/code/src/test/java/io/confluent/developer/KafkaProducerApplicationTest.java
message-ordering/kafka/code/src/main/java/io/confluent/developer/KafkaProducerApplication.java
naming-changelog-repartition-topics/kstreams/code/src/main/java/io/confluent/developer/NamingChangelogAndRepartitionTopics.java
serialization/kstreams/code/src/test/java/io/confluent/developer/serialization/SerializationTutorialTest.java
serialization/kstreams/code/src/main/java/io/confluent/developer/serialization/SerializationTutorial.java
serialization/kstreams/markup/dev/make-topology.adoc
splitting/kstreams/code/src/test/java/io/confluent/developer/SplitStreamTest.java
splitting/kstreams/code/src/main/java/io/confluent/developer/SplitStream.java
streams-to-table/kstreams/code/src/test/java/io/confluent/developer/StreamsToTableTest.java
streams-to-table/kstreams/code/src/main/java/io/confluent/developer/StreamsToTable.java
time-concepts/ksql/code/src/main/java/io/confluent/developer/KafkaProducerDevice.java
transforming/kafka/code/src/test/java/io/confluent/developer/TransformEventsTest.java
transforming/kafka/code/src/main/java/io/confluent/developer/TransformEvents.java
transforming/kstreams/code/src/test/java/io/confluent/developer/TransformStreamTest.java
transforming/kstreams/code/src/main/java/io/confluent/developer/TransformStream.java
tumbling-windows/kstreams/code/src/test/java/io/confluent/developer/TumblingWindowTest.java
tumbling-windows/kstreams/code/src/main/java/io/confluent/developer/TumblingWindow.java