Fix link to documentation.

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Move TODO, HOWTO web-related items to web branch.
Merge branch 'master' of https://github.com/milewgit/tchart

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Add web site-related CHECKLIST items.

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Remove README-related tasks from Rakefile.

These are now in the gh-pages Rakefile.

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Add project website to HISTORY.
# [ci skip]
Improve new README.

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