general work

- renamed nunjucks extension to njk
- removed old demo html files
- started to change CRLF to LF
- detail work on style definitions
- added structure for demo files

source/pages/blank.njk

@@ -0,0 +1,11 @@
+<!-- blank.njk -->
+{% set pageId = "blank" %}
+{% set pageClass = "height_full" %}
+
+{% extends "default.njk" %}
+
+{% block title %}blank{% endblock %}
+
+{% block body_content %}
+
+{% endblock %}