minor updates to codefolding readme

mainly nbconvert_support

src/jupyter_contrib_nbextensions/nbextensions/codefolding/readme.md

@@ -1,60 +1,79 @@
 Codefolding
 ===========
+
 This extension adds codefolding functionality from CodeMirror to a codecell.
 
 After clicking on the gutter (left margin of codecell) or typing `Alt+F`, the code gets folded. See the examples below. The folding status is saved in the cell metadata of the notebook, so reloading of a notebook will restore the folding view.
 
 Supported modes
 ---------------
+
 Three different folding modes are supported:
 
+
 ### Indent Folding
+
 Python-style code folding, detetects indented code.
 ![Unfolded](codefolding_indent_unfolded.png)
 
 The unfolded code above can be folded like this:
+
 ![](codefolding_indent_folded_1.png)
 
 or this:
+
 ![](codefolding_indent_folded_2.png)
 
 
 ### Bracket Folding
+
 Other languages like Javascript use brackets to designate code blocks. Codefolding is supported for Javascript in using the `%%javascript` magic in a codecell.
 
+
 ### Firstline Comment Folding
+
 Allows collapsing of Python code cells to a single comment line. This is useful for long codecells. The algorithm simply looks for a comment in the first line and allows folding in the rest of the cell.
+
 ![](codefolding_firstline_unfolded.png)
 
 The code above can be folded like this:
+
 ![](codefolding_firstline_folded.png)
 
 
 ### Magics Folding
+
 If you specify a magic in the first line of a cell, it can be folded, too.
+
 ![](magic-unfolded.png)
 
 Folded:
+
 ![](magic-folded.png)
 
 
 Internals
 ---------
+
 When saving a notebook, the folding information is saved in the metadata of each codecell. 
 The number of the folding start line (beginning with 0) is stored in an array: 
 
 ```javascript
 cell.metadata.code_folding = [ 3, 20, 33 ]
 ```
+
 When reloading the notebook, the folding status is restored.
 
+
 Exporting
 ---------
+
 To export a notebook containing folded cells, you will need to apply a custom preprocessor for nbconvert. 
-The preprocessor is located in `nbconvert_support/pre_codefolding.py`.
+The preprocessor is located in `jupyter_contrib_nbextensions/nbconvert_support/pre_codefolding.py`.
 
 The preprocessor is installed when you install the jupyter_contrib_nbextensions package.
 To activate the preprocessor manually, add the following lines to `jupyter_nbconvert_config.py`:
-```javascript
-Exporter.preprocessors ='pre_codefolding.CodeFoldingPreprocessor'
+
+```python
+Exporter.preprocessors += ['jupyter_contrib_nbextensions.nbconvert_support.CodeFoldingPreprocessor']
 ```