Document -W in clang --help. Also make the help text more consistent (don't end descriptions in periods, use | to separate possible values).
Document -W in clang --help. Also make the help text more consistent (don't end descriptions in periods, use | to separate possible values).


git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@167645 91177308-0d34-0410-b5e6-96231b3b80d8

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