Updated mediawiki/extensions
Project: mediawiki/extensions/Echo  b487bb5c86f42555188d18dc1dff2b27dcd2b0df

Allow custom 'diff' values to be set

So we can link to multiple edits at once. This should not
change any existing behavior since 'prev' is used if nothing
is set.

Change-Id: If79e041d1443d8360abdf60b513ce8c7c0c7e1f8