Auto merge of #296 - servo:pin-nightly-drop-glue, r=nox

Pin the nightly version on Travis and AppVeyor.

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Author: bors-servo

.travis.yml

@@ -2,7 +2,7 @@ language: rust
 sudo: 9000
 dist: trusty
 rust:
-  - nightly
+  - nightly-2016-08-23
 os:
   - linux
   - osx

appveyor.yml

@@ -39,7 +39,7 @@ environment:
 install:
   - ps: Start-FileDownload "http://servo-rust.s3.amazonaws.com/build/MozillaBuildSetup-2.2.0.exe"
   - ps: .\MozillaBuildSetup-2.2.0.exe /S | Out-Null
-  - ps: Start-FileDownload "https://static.rust-lang.org/dist/rust-${env:TARGET}.exe" -FileName "rust-install.exe"
+  - ps: Start-FileDownload "https://static.rust-lang.org/dist/2016-08-23/rust-${env:TARGET}.exe" -FileName "rust-install.exe"
   - ps: .\rust-install.exe /VERYSILENT /NORESTART /DIR="C:\rust" | Out-Null
   - ps: $env:PATH="$env:PATH;C:\rust\bin"
 # I can't make this work with a multi-line script (e.g. via |+ etc.), so we copy the if before every command