* make colors configurable (use .rc file?)

* do some smashing things with comments

* canonicalize the order of attributes

* pxml of the following is not so nice:

    <?xml version="1.0" encoding="utf-8"?>
    <!DOCTYPE document PUBLIC "+//IDN docutils.sourceforge.net//DTD Docutils Generic//EN//XML" "http://docutils.sourceforge.net/docs/ref/docutils.dtd">
    <!-- Generated by Docutils 0.10 -->
    <document ids="local-top-level" names="local\ top-level" source="&lt;string&gt;" title="Local Top-Level"><title>Local Top-Level</title><paragraph>some text</paragraph></document>

* pxml of the following incorrectly adds whitespace, from:

    <document classes="extension math" ids="local-top-level-10" names="local\ top-level\ 10" source="&lt;string&gt;" title="Local Top-Level 10"><title>Local <emphasis>Top-Level</emphasis> 10</title><paragraph>some text</paragraph><section ids="sub-title" names="sub-title"><title>Sub-Title</title><paragraph>more text</paragraph></section></document>
  to:
    <document classes="extension math" ids="local-top-level-10" names="local\ top-level\ 10" source="&lt;string&gt;" title="Local Top-Level 10">
      <title>Local <emphasis>Top-Level</emphasis> 10
      </title>
      <paragraph>some text</paragraph>
      <section ids="sub-title" names="sub-title">
        <title>Sub-Title</title>
        <paragraph>more text</paragraph>
      </section>
    </document>

* get rid of this error during installation:

    Installed ./virtualenv/lib/python2.7/site-packages/pxml-0.2.10-py2.7.egg
    Processing dependencies for pxml==0.2.10
    Finished processing dependencies for pxml==0.2.10
    Error in atexit._run_exitfuncs:
    Traceback (most recent call last):
      File "/usr/lib/python2.7/atexit.py", line 24, in _run_exitfuncs
        func(*targs, **kargs)
      File "/usr/lib/python2.7/multiprocessing/util.py", line 284, in _exit_function
        info('process shutting down')
    TypeError: 'NoneType' object is not callable
    Error in sys.exitfunc:
    Traceback (most recent call last):
      File "/usr/lib/python2.7/atexit.py", line 24, in _run_exitfuncs
        func(*targs, **kargs)
      File "/usr/lib/python2.7/multiprocessing/util.py", line 284, in _exit_function
        info('process shutting down')
    TypeError: 'NoneType' object is not callable
