Add Basic Web Interface/Admin View Code + Small Changes

Summary of Changes
-----------------------------
```
Small changes:
- Update .gitignore to ignore common temporary or generated files
- Remove references to old RAINS-Agent name in .gitignore and pom.xml
- Declare Apache Jena as Maevan dependency
- Misc. changes to ApplicationConfig.java, context.xml, 
  and nb-configuration.xml, generated by Netbeans IDE
- Organize files into data/, js/, css/, resources/, and WEB-INF/jsp/ folders
- Add cropped version of app.gif icon
- Add library resources and license files of libraries used
  - Twitter Bootstrap (MIT)
  - d3.js (BSD)
  - d3.slider.js (BSD)
```
```
Basic web interface code:
- Add mockup of landing page index.html
- Add basic servlet/jsp webapp structure
  - index.html (login form) --> LoginServlet.java
  - LoginServlet.java (preprocess) --> login.jsp
  - login.jsp (temporary forward) --> parser.jsp
  - parser.jsp parses .ttl files and returns JSON output
```
```
Basic admin view code:
- Add small and large data sets (*.ttl, *.json in data folder) for testing purposes
- Add test.html which displays a graph representation of a Turtle file (work in progress)
```