Update docs.

Fixes typos.
Fixes #3202.

[SVN r54206]

libs/type_traits

@@ -1 +1 @@
-Subproject commit 68a4a628cfc8ebf11e4ec4b3a18fa9d4ccf4f548
+Subproject commit 28ddc6e6f55cd187a2f7264ae3b1624d2634fd1d