Add some basic usage in doc

README.md

@@ -0,0 +1,57 @@
+## Basic examples
+
+### Hello World
+
+```python
+from rtfng.Elements import Document, Section
+
+doc = Document()
+section = Section()
+section.append('Hello world !')
+doc.Sections.append(section)
+
+doc.write(file('hello.rtf', 'w'))
+```
+
+### Example 1
+
+```python
+from rtfng.Elements import Document, Section
+from rtfng.document.paragraph import Paragraph
+from rtfng.document.character import TEXT
+
+# Init
+doc = Document()
+section = Section()
+
+# First paragraph
+p = Paragraph()
+p.append('It is also possible to manully override a style:',
+          TEXT(' this is a change of the font size', size=48),
+         '.')
+section.append(p)
+
+# Empty paragraph
+section.append('')
+
+# Second paragraph
+p = Paragraph()
+p.append('This is a ',
+          TEXT('very important information !', colour=doc.StyleSheet.Colours.Red, underline=True, bold=True)
+        )
+# Have a look to TEXT() definition in rtfng/document/character.py for more options
+
+section.append(p)
+doc.Sections.append(section)
+
+doc.write(file('example.rtf', 'w'))
+```
+
+## Tests
+
+For example usage, see the code in the unit tests in the 'test' directory and its subdirectories.
+
+To run all tests:
+
+    python test/test_all.py
+    python test/test_doctests.py