Email from Kevin:.

I was creating a "config" file to be used in all the documents in a
project and one thing I wanted to do was "auto-anchor" titles.

I have titles like so:
= An Awesome Heading =

and I have the following preproc so far:
%%!preproc: '^=+(.*?)=+$' '\g<0>[\1]'

This gets me this far:
= An Awesome Heading =[ An Awesome Heading ]

...

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This is a great feature o implement in the core.

Every title should be anchored automatically, and the user, of course, can 
overwrite it with the [anchor].

We need to create a new function to make a "slug" from the text: convert to 
lower case, change spaces and punctuation to hyphens, unaccent chars (á -> a). 
For example:

>>> get_anchor("Hello João, nice hat!!!")
hello-joao-nice-hat
>>>

I'm sure such a function was already implemented countless times, not let's not 
reinvent the wheel. I know Python's docutils have it, maybe we can copy it.