Use Blockly.blocks.* for blocks modules, leaving the Blockly.Blocks
name for the block dictionary object.
This resolves a problem with advanced compilation of Blockly Games,
where, in the compressed output, (the minified name of)
Blockly.Blocks gets overwritten, with the dictionary object defined in
core/blocks.js being replaced by an empty namespace object
created by the provides of Blockly.Blocks.* in blocks/*.js. Without
this fix, some block definitions end up being created in the
dictionary and some on the namespace object—with chaos
predictably ensuing.
