Summary: fixed very old document

Reviewers: tejohnson, pcc

Subscribers: mehdi_amini, eraman, llvm-commits

Differential Revision: http://reviews.llvm.org/D22121

llvm-svn: 274811

Fix defininitions->definitions.

Reviewed by David Blaikie.

llvm-svn: 223216

Before we learned about :doc:, we used :ref: and put a dummy link at the
top of each page. Don't do that anymore.

This fixes PR14891 as a special case.

llvm-svn: 172162

llvm-svn: 169990

llvm-svn: 165198

llvm-svn: 158808