Fix a misspelling in the documentation.

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and place it under your choice of the public domain / CC-Zero / the MIT X11
licence / the LGPL v2-or-above / the GPL v2-or-above / any other licence
of your choice.

Nevertheless, I would appreciate if you credit me (Shlomi Fish, whose
home page is http://www.shlomifish.org/ ).
Merge pull request #11 from shlomif/shlomif_typos_fixes

Fix a misspelling in the documentation.