Squashed commit of the following:

commit df48c4827e05243c137187bb0d9f157327c26b86
Author: Milind Barve <milind@datatorrent.com>
Date:   Tue Apr 1 15:04:51 2014 +0530

    Demo guide for Yahoo finance with Derby SQL demo application. #MLHR-982

commit 7b1ced0d7a18ff68c163b0b6c6628702649e1e63
Author: Milind Barve <milind@datatorrent.com>
Date:   Tue Apr 1 15:04:16 2014 +0530

    Demo guide for Yahoo finance with Alerts demo application. #MLHR-980

commit c43465d8f8235b5049bf71a30e5b95702a6f2153
Author: Milind Barve <milind@datatorrent.com>
Date:   Tue Apr 1 15:00:15 2014 +0530

    Demo guide for Yahoo finance demo application. #MLHR-981
MLHR-1073 #resolve Handle multiple unified group elements in a set
make BufferedReader transient
fix compile eror
advancing batch start by num events
reset batch start index in end window
TwitterTopCounter doc fix
Merge pull request #924 from PramodSSImmaneni/MLHR-1073

MLHR-1073 #resolve Handle multiple unified group elements in a set
Merge branch 'MLHR-982_pull' of https://github.com/milindbee/Malhar
publish test jar
Merge branch 'master' of github.com:DataTorrent/Malhar
Make createTopic public.
Merging dimension computation changes from ETL to master
don't leak twitter dependency
Make basedir for embedded Kafka server configurable.
Remove assumptions in test consumer and producer to allow for use in other tests.
removed travis script handling old ui location
Merge pull request #932 from siyuanh/dt-dev

Upgrade operator to use kafka 0.8.1.1
changed to compile by doing Stats.CustomStats to Context.Counters migration
aggregated counters in the listener