add demo section and add search and NLP demos

_config.yml

@@ -11,6 +11,7 @@ forumurl: 'https://forum.meta-toolkit.org'
 
 # Default categories (in order) to appear in the navigation
 sections: [
+    ['demo', 'Demos'],
     ['tut', 'Tutorials']
 ]
 

_layouts/page.html

@@ -3,7 +3,7 @@
 ---
 
 <div class=page-header>
-    <h2>{{ page.title }}
+    <h2>{% if page.category == 'demo' %}Demo: {% endif %}{{ page.title }}
         {% if page.subtitle %}<small>{{ page.subtitle }}</small>{% endif %}
     </h2>
 </div>

css/main.css

@@ -18,6 +18,12 @@ code {
     color: inherit;
 }
 
+img {
+    display: block;
+    margin-left: auto;
+    margin-right: auto;
+}
+
 /* see:
  * http://stackoverflow.com/questions/18329010/what-happened-to-nav-header-class
  */

nlp-demo.md

@@ -0,0 +1,24 @@
+---
+title: Natural Language Processing
+layout: page
+category: demo
+order: 2
+---
+
+The MeTA NLP demo is currently located at
+[http://timan103.cs.illinois.edu/nlp-demo/](http://timan103.cs.illinois.edu/nlp-demo/).
+
+This demo first segments sentences with the ICU tokenizer. Then, it runs
+part-of-speech tagging and a grammatical parser. It displays these outputs for
+each sentence.
+
+The demo code can be found [online on
+GitHub](https://github.com/meta-toolkit/nlp-demo) in the [MeTA toolkit
+organization](https://github.com/meta-toolkit). It makes use of a very simple
+[HTTP server](https://github.com/meta-toolkit/simple-http-server) to connect the
+back end to the front end.
+
+Below is the output of running the demo with the input text "Here's a short
+sentence. This is part of the demo."
+
+![NLP demo](nlp-demo.png)

search-demo.md

@@ -0,0 +1,23 @@
+---
+title: Search Engine and Rankers
+layout: page
+category: demo
+order: 1
+---
+
+The MeTA search and ranking demo is currently located at
+[http://timan103.cs.illinois.edu/search-app/](http://timan103.cs.illinois.edu/search-app/).
+
+The search engine is over Wikipedia articles with article titles as metadata.
+Selecting a ranker from the dropdown on the left of the search bar changes the
+ranking function that is used to score each document. The numbers to the right
+of each document are the score that the ranker has given it. Clicking on a link
+will open the respective Wikipedia article.
+
+The demo code can be found [online on
+GitHub](https://github.com/meta-toolkit/search-app) in the [MeTA toolkit
+organization](https://github.com/meta-toolkit). It makes use of a very simple
+[HTTP server](https://github.com/meta-toolkit/simple-http-server) to connect the
+back end to the front end.
+
+![Search demo](search-demo.png)