This commit adds block-level settings in the core. Block level settings allow a block to define the preset settings of its nested blocks using the same shape as theme.json.
Props oandregal, Mamaduka, jorgefilipecosta, dmsnell, adamziel.
57651 #57651.
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git-svn-id: http://core.svn.wordpress.org/trunk@54788 1a063a9b-81f0-0310-95a4-ce76da25c4cd