Chameleon

---------------------

Bugfixes:

- The tab character (``\t``) is now parsed correctly when used inside
tags.

Features:

- The ``RepeatDict`` class now works as a proxy behind a separate
dictionary instance.

- Added template constructor option ``keep_body`` which is a flag
(also available as a class attribute) that controls whether to save
the template body input in the ``body`` attribute.

This is disabled by default, unless debug-mode is enabled.

- The page template loader class now accepts an optional ``formats``
argument which can be used to select an alternative template class.

---------------------

Bugfixes:

- The backslash character (followed by optional whitespace and a line
break) was not correctly interpreted as a continuation for Python
expressions.

Features:

- The Python expression implementation is now more flexible for
external subclassing via a new ``parse`` method.

---------------------

Bugfixes:

- Initial keyword arguments passed to a template now no longer "leak"
into the template variable space after a macro call.

- An unexpected end tag is now an unrecoverable error.

Features:

- Improve exception output.

---------------------

Bugfixes:

- Fixed issue where variable names that begin with an underscore were
seemingly allowed, but their use resulted in a compiler error.

Features:

- Template variable names are now allowed to be prefixed with a single
underscore, but not two or more (reserved for internal use).

Examples of valid names::

item
ITEM
_item
camelCase
underscore_delimited
help

- Added support for Genshi's comment "drop" syntax::

<!--! This comment will be dropped -->

Note the additional exclamation (!) character.

This fixes addresses issue 10.

---------------------

Bugfixes:

- The ``tal:attributes`` statement now correctly operates
case-insensitive. The attribute name given in the statement will
replace an existing attribute with the same name, without respect to
case.

Features:

- Added ``meta:interpolation`` statement to control expression
interpolation setting.

Strings that disable the setting: ``"off"`` and ``"false"``.
Strings that enable the setting: ``"on"`` and ``"true"``.

- Expression interpolation now works inside XML comments.

--------------------

Features:

- Better debugging support for string decode and conversion. If a
naive join fails, each element in the output will now be attempted
coerced to unicode to try and trigger the failure near to the bad
string.