[PATCH] [libcxx] Update libc++ docs to include instructions for LIT.

[Dan Albert]

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Comment at: www/index.html:206
@@ +205,3 @@
+  </ul>
+  <p>The above is currently quite inconvenient. Sorry! We're working on it!</p>
+
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Nico Weber wrote:
> How much work is it to not require people to change lit.site.cfg? The `ln -s` is a bit gnarly, it'd be nice if it wouldn't have to be in the docs.
I haven't really looked in to that yet. One obvious solution is to just have cmake do the symlink for you (probably by generating the lit.site.cfg in place and creating the symlink in build/test/). It'll be another patch though. I'll make sure I update the docs when I do fix this.

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Comment at: www/index.html:213
@@ +212,3 @@
+  </p>
+
+  <!--=====================================================================-->
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Marshall Clow wrote:
> I would add something here about using DYLD_LIBRARY_PATH to interpose the newly built dylib (say, for testing purposes).
> 
> Should probably remind people that (on a Mac) blindly copying these dylibs to /usr/lib will, if any error occurs, result in a system that will not boot.
The former is down below under "Using libc++ in your programs" (not obvious from the diff, but pretty clear on the webpage). I've added the extra warning for Mac.

http://reviews.llvm.org/D4766