fix bad rendering of the changelog for the alias grammar changes

[ghost]

So the grammar block is not well rendered, I don't know why. Never mind, I remove it because the changelog has never exposed a $(GRAMMAR ) block to this date. Just a link will be fine for those who are interested.

@wilzbach, you still need to enable markdown preview when the change log is rendered. I tried to do it but the 1000 lines makefile of dlang.org repo causes me allergic reactions.

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[wilzbach]

@wilzbach, you still need to enable markdown preview when the change log is rendered.

IIRC @dgileadi was/is on this (enabling the markdown preview for dlang.org)

[ghost]

@thewilsonator merge now ? Just rebased and squashed.