added tt recipe cleaning data with spreadsheets
Update text/recipes/sql-for-data-manipulation.rst

The bulk of this commit is so that the Markdown to rST conversion
functions properly. rST does not appear to allow HTML in literal
blocks, like Markdown. This left the output very messy.

Other changes:

 * improved intro text, as much of the text about the data source
   appears to have been removed by a previous edit
 * I have converted <abbr title="comment"></abbr> to SQL comments
   where relevant, but have edited most of them away.
 * Changed Google Refine to Open Refine
 * General formatting improvements 
Update text/recipes/cleaning-data-with-spreadsheets.rst
Merge pull request #52 from emmaprest/patch-1

Update text/recipes/cleaning-data-with-spreadsheets.rst
nuts and chewing gum