added Organizing Programs Without Classes and updated README
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Add Gittip widget.
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Merge pull request #133 from DarrenN/organizing-programs-without-classes

Added Organizing Programs Without Classes and updated README
Updated README
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Create README.md
Create README.md
Added headling
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Update README.md
Merge pull request #135 from DarrenN/apis

Updated README for api_design
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Hints for computer system design @doothings PWL#1
Merge pull request #136 from doothings/master

Hints for computer system design @doothings PWL#1
Update README.md
Fixed broken link in 'The Rendering Equation'
Merge pull request #138 from cuevasclemente/fix_rendering

Fixed broken link in 'The Rendering Equation'