CDAP-538: Ported procedures of WordCount app to services.
Merge branch 'develop' into CDAP-538-word-count-app

Conflicts:
	cdap-examples/WordCount/src/main/java/co/cask/cdap/examples/wordcount/WordCount.java
CDAP-538: Updated docs and scripts.
CDAP-538: Added endpoint to retrieve word count with default limit equal 10; Minor code/docs updates.
Merge remote-tracking branch 'upstream/develop' into CDAP-538-word-count-app
Merge remote-tracking branch 'upstream/develop' into CDAP-538-word-count-app
CDAP-538: Updated tests to wait service startup with timeout; Minor updated calculation of average length.
CDAP-538: Removed TODO; Replaced service startup check to private method.
CDAP-538: Updated docs of WordCount app.
Merge remote-tracking branch 'upstream/develop' into CDAP-538-word-count-app
CDAP-538: Used method from TestFrameworkTest to wait service startup.
CDAP-538: Updated RetrieveCountsHandler.getCount(...) method to use QueryParam for optional limit param.
Merge remote-tracking branch 'upstream/develop' into CDAP-538-word-count-app
CDAP-538: Used Integer instead of int to save possibility set limit to zero.
Merge remote-tracking branch 'upstream/develop' into CDAP-538-word-count-app
[CDAP-505] Added IdentityStreamEventDecoder
Merge remote-tracking branch 'upstream/develop' into CDAP-538-word-count-app
(CDAP-355) Insecurely pass user id from router to downstream services
Merge pull request #137 from caskdata/feature/router-pass-user

(CDAP-355) Insecurely pass user id from router to downstream services
CDAP-538: Reverted to the PathParam instead of QueryParam.