This to support GAE which can't run markupsafe.
  [ticket:151] No idea whatsoever if the
  install_requires in setup.py also breaks GAE,
  couldn't get an answer on this.

doesn't occur on Python 2.7

  such as <%foo:bar x="${...}">, now
  allow multiline Python expressions.

  for the `file` argument, i.e. with ${}.
  The `context` variable, if needed,
  must be referenced explicitly.
  [ticket:141]

- Fixed previously non-covered regular
  expression, such that using a ${} expression
  inside of a tag element that doesn't allow
  them raises a CompileException instead of
  silently failing.

  i.e. in place of cgi.escape().  Faster
  C-based implementation and also escapes
  single quotes for additional security.
  Supports the __html__ attribute for
  the given expression as well.

  When using "disable_unicode" mode,
  a pure Python HTML escaper function
  is used which also quotes single quotes.

  Note that Pylons by default doesn't
  use Mako's filter - check your
  environment.py file.

  exceptions.text_error_template which
  is not Py3k compatible.  [ticket:137]

  such that if no traceback is passed
  and sys.exc_info() has been reset,
  the formatter just returns blank
  for the "traceback" portion.
  [ticket:135]
- some long line cleanup

  where the source is stored temporarily is
  now made in the same directory as that of
  the .py file.  This ensures that the two
  files share the same filesystem, thus
  avoiding cross-filesystem synchronization
  issues.  Thanks to Charles Cazabon.

  line contains no line number, as in when
  inside an eval/exec-generated function.
  [ticket:132]

  template.last_modified

  exc.__class__.__name__
  in html/text error templates when using
  Python 2.4 [ticket:131]

  template.get_def(...).render() now checks the
  argument signature the same way as it did in
  0.2.5, so that TypeError is not raised.
  reopen of [ticket:116]

  [ticket:129]

  a given path that is a directory, not a filename,
  instead of passing through to the template to
  generate IOError.  [ticket:73]

  is passed only an absolute filename (i.e. with c:
  drive etc.)  and no URI - the URI is converted
  to a forward-slash path and module_directory
  is treated as a windows path.  [ticket:128]

  uncommon feature, have been improved.  The defs
  no longer get doubly-rendered in the body() scope,
  and now allow local variable assignment without
  breakage.  [ticket:109]

- cleanup

  inheriting template - the full set of render()
  arguments are passed down through the inherits
  chain.  Undeclared arguments go into **pageargs
  as usual.  [ticket:116]

  % if: %endif, etc. [ticket:94]
- finished cleanup for codegen.py, [ticket:98]

  non-whitespace character on a line by escaping
  it as in "%%". [ticket:112]

  text_error_template().render() now accept "error"
  and "traceback" as optional arguments, and
  these are now actually used.  [ticket:122]