doc: Use lowercase types where primitives (not objects) are expected

Fixed:
* ve.dm.MetaList.js (added in I74a9a2139)
* ve.ce.Document.js (added in Ifc01b8e5d)

Change-Id: Id758818ded5b892233bfc0d62f0f435da480c950
Merge "doc: Use lowercase types where primitives (not objects) are expected"