docs for tagstring-parsing updates

docs/changelog.txt

+Changelog
+=========
+
+master (unreleased)
+~~~~~~~~~~~~~~~~~~~
+
+* Smarter tagstring parsing for form field; ported from Jonathan
+  Buchanan's `django-tagging
+  <http://django-tagging.googlecode.com>`_. Now supports tags
+  containing commas. See :ref:`tags-in-forms` for details.

docs/forms.txt

+.. _tags-in-forms:
+
+Tags in forms
+=============
+
+The ``TaggableManager`` will show up automatically as a field in a
+``ModelForm`` or in the admin. Tag input via the form field is parsed
+as follows:
+
+* If the input doesn't contain any commas or double quotes, it is simply
+  treated as a space-delimited list of tag names.
+
+* If the input does contain either of these characters:
+
+  * Groups of characters which appear between double quotes take
+    precedence as multi-word tags (so double quoted tag names may
+    contain commas). An unclosed double quote will be ignored.
+
+  * Otherwise, if there are any unquoted commas in the input, it will
+    be treated as comma-delimited. If not, it will be treated as
+    space-delimited.
+
+Examples:
+
+====================== ======================================= ================================================
+Tag input string       Resulting tags                          Notes
+====================== ======================================= ================================================
+apple ball cat         [``apple``], [``ball``], [``cat``]      No commas, so space delimited
+apple, ball cat        [``apple``], [``ball cat``]             Comma present, so comma delimited
+"apple, ball" cat dog  [``apple, ball``], [``cat``], [``dog``] All commas are quoted, so space delimited
+"apple, ball", cat dog [``apple, ball``], [``cat dog``]        Contains an unquoted comma, so comma delimited
+apple "ball cat" dog   [``apple``], [``ball cat``], [``dog``]  No commas, so space delimited
+"apple" "ball dog      [``apple``], [``ball``], [``dog``]      Unclosed double quote is ignored
+====================== ======================================= ================================================
+

docs/getting_started.txt

@@ -19,3 +19,4 @@ And then to any model you want tagging on do the following::
         # ... fields here
 
         tags = TaggableManager()
+

docs/index.txt

@@ -11,9 +11,11 @@ for known issues with older versions of Django), and Python 2.4-2.X.
    :maxdepth: 2
    
    getting_started
+   forms
    api
    custom_through
    issues
+   changelog
 
 Indices and tables
 ==================