DOC: Two small doc changes.

src/caosadvancedtools/cfood.py

@@ -152,9 +152,19 @@ fileguide = FileGuide()
 
 
 class AbstractCFood(object, metaclass=ABCMeta):
+    """ Abstract base class for Crawler food (CFood)."""
 
     def __init__(self, item):
-        """ Abstract base class for Crawler food (CFood)."""
+        """A CFood has two main methods which must be customized:
+
+    1. `create_identifiables`
+        This method defines (and inserts if necessary) the identifiables which may be updated at a
+        later stage.  After calling this method, the `identifiables` Container contains those
+        Records which will be updated at a later time.
+
+    2. `update_identifiables`
+        This method updates the stored identifiables as necessary.
+        """
         self.to_be_updated = db.Container()
         self.identifiables = db.Container()
         self.item = item

src/doc/crawler.rst

@@ -71,7 +71,7 @@ indicated in the messages).
 Invocation as Python Script
 ---------------------------
 
-The crawler can be executed directly via a python script (usually called
+The crawler can be executed directly via a Python script (usually called
 ``crawl.py``). The script prints the progress and reports potential
 problems. The exact behavior depends on your setup. However, you can
 have a look at the example in the
@@ -84,7 +84,7 @@ have a look at the example in the
 Call ``python3 crawl.py --help`` to see what parameters can be provided.
 Typically, an invocation looks like:
 
-.. code:: python
+.. code:: sh
 
    python3 crawl.py /someplace/