Fix link in stdlib main page docs

[steveklabnik]

No description provided.

[rust-highfive]

r? @alexcrichton

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[alexcrichton]

@bors: r+ c40708d rollup

[bors]

⌛ Testing commit c40708d with merge 15e8ca3...

[bors]

💔 Test failed - auto-mac-32-opt

[alexcrichton]

@bors: retry

On Sat, May 16, 2015 at 9:06 AM, bors notifications@github.com wrote:

[image: 💔] Test failed - auto-mac-32-opt
http://buildbot.rust-lang.org/builders/auto-mac-32-opt/builds/5012

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Reply to this email directly or view it on GitHub
#25454 (comment).

[bors]

⌛ Testing commit c40708d with merge 098d58f...

[bors]

💔 Test failed - auto-linux-32-nopt-t

[alexcrichton]

@bors: retry

On Sat, May 16, 2015 at 11:13 PM, bors notifications@github.com wrote:

[image: 💔] Test failed - auto-linux-32-nopt-t
http://buildbot.rust-lang.org/builders/auto-linux-32-nopt-t/builds/4989

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Reply to this email directly or view it on GitHub
#25454 (comment).

[bors]

⌛ Testing commit c40708d with merge 1c44801...

[bors]

☀️ Test successful - auto-linux-32-nopt-t, auto-linux-32-opt, auto-linux-64-nopt-t, auto-linux-64-opt, auto-linux-64-x-android-t, auto-mac-32-opt, auto-mac-64-nopt-t, auto-mac-64-opt, auto-win-32-nopt-t, auto-win-32-opt, auto-win-64-nopt-t, auto-win-64-opt