[DOC-FAQ] Add How to add new package/grid.

See Issue  FAQ: How to request for new lines in a grid #283 .

[]Question, why does Github claim that this line has a diff?
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-We've had the odd request for Gitorious support. Their API is adequate and we welcome pull requests.
+We've had the odd request for Gitorious support. Their API is adequate and we welcome pull requests.
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