This function works like image_url() in that it expects the image to be a path relative to the images directory.
There are clear advantages and disadvantages to this approach.
See http://en.wikipedia.org/wiki/Data_URI_scheme for more details.
NOTE: Neither IE6 nor IE7 support data urls.
Using this approach with large images is discouraged.
YUI doesn't even consider it part of the reset. With so much
disagreement, I decided to make the compass reset agnostic and let
individual frameworks decide what the body line-height ought to be.
Breakdown of changes:
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Remove the body scope that is unnecessarily added to many blueprint classes due to the way the mixins were constructed and used. Blueprint mixins that operate on the body tag now follow a pattern where they take the body selector as an argument and must always be mixed into the top level of a stylesheet. The classes will be scoped whenever the selector is not a simple "body" selector which is the default. Mixins affected: +blueprint-ie, +blueprint-print, +blueprint-typography, and +blueprint-scaffolding. All of these mixins use corresponding +[mixin]-body and +[mixin]-defaults mixins in their implementations that you can use directly if you feel constrained by the requirement to mix into the top-level.
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Made all configurable constants possible to override in a base stylesheet using conditional assignment. Moved many colors that were still hard coded to the colors.sass module so they can be overridden.
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Restored some blueprint defaults even though I didn't like them. With the exception of the blueprint link urls which are now available as a mixin called +blueprint-show-link-urls (they used to just be commented out.)
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Grid constants have been renamed in both the grid and liquid grid modules. These constants are now conditionally assigned to make the grid easily configured.
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The liquid grid now uses the compass clearfix.
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moved the primary mixin for a module (where one exists) to the top of the file for clarity of readers.
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blueprint grid classes are now appropriately scoped under the .container class.
