updated the documentation
addressed compiler warnings
a ton of UI enhancements, including:
1. One unified mechanism for hiding/showing empty topics
2. Addressed display issues with streaming Topics and Consumers
removed the first offset label and output field
Merge branch 'feature/webui' into scala_2.11

* feature/webui:
  removed the first offset label and output field
  a ton of UI enhancements, including: 1. One unified mechanism for hiding/showing empty topics 2. Addressed display issues with streaming Topics and Consumers
  addressed compiler warnings
  updated the documentation