more unit test and refactor
	modified:   src/main/java/org/ananth/waroftitans/analyser/EntityTransformFunction.java
	modified:   src/main/java/org/ananth/waroftitans/twitter/TweetTextBuilder.java
	modified:   src/main/java/org/ananth/waroftitans/twitter/streaming/TwitterStatusListenerImpl.java
	modified:   src/test/java/org/ananth/waroftitans/analyser/SentimentAnalyzerFunctionTest.java
	modified:   src/test/java/org/ananth/waroftitans/twitter/TweetTextBuilderTest.java