split 1st paragraph, removed repeditive 'documentation'

ref #1

I remember an English teacher would red-mark my papers if I used the same word 3 times almost in a row ;).
Rebased
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https://github.com/paulirish/w3fools/pull/57#issuecomment-45027843

Seemed good in Firebug.
Merge branch 'tomByrer-patch-1'
Merge pull request #5 from tomByrer/patch-2

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