Add installation links to v0.4-rc4 toolchains. (tensorflow#220)

swiftlang/swift@7d157f3

Installation.md

@@ -8,16 +8,23 @@ To install Swift for TensorFlow, download one of the packages below and follow t
 
 ## Releases
 
+| Download | Version | Date |
+|----------|---------|------|
+| [Xcode 11 beta](https://storage.googleapis.com/swift-tensorflow-artifacts/releases/v0.4/rc4/swift-tensorflow-RELEASE-0.4-osx.pkg) | v0.4.0-rc4 | July 25, 2019 |
+| [Ubuntu 18.04 (CPU Only)](https://storage.googleapis.com/swift-tensorflow-artifacts/releases/v0.4/rc4/swift-tensorflow-RELEASE-0.4-ubuntu18.04.tar.gz) | v0.4.0-rc4 | July 25, 2019 |
+| [Ubuntu 18.04 (CUDA 10.0)](https://storage.googleapis.com/swift-tensorflow-artifacts/releases/v0.4/rc4/swift-tensorflow-RELEASE-0.4-cuda10.0-cudnn7-ubuntu18.04.tar.gz) | v0.4.0-rc4 | July 25, 2019 |
+| [Ubuntu 18.04 (CUDA 9.2)](https://storage.googleapis.com/swift-tensorflow-artifacts/releases/v0.4/rc4/swift-tensorflow-RELEASE-0.4-cuda9.2-cudnn7-ubuntu18.04.tar.gz) | v0.4.0-rc4 | July 25, 2019 |
+
+<details>
+  <summary>Older Packages</summary>
+
 | Download | Version | Date |
 |----------|---------|------|
 | [Xcode 11 beta](https://storage.googleapis.com/swift-tensorflow-artifacts/releases/v0.4/rc2/swift-tensorflow-RELEASE-0.4-osx.pkg) | v0.4.0-rc2 | July 10, 2019 |
 | [Ubuntu 18.04 (CPU Only)](https://storage.googleapis.com/swift-tensorflow-artifacts/releases/v0.4/rc2/swift-tensorflow-RELEASE-0.4-ubuntu18.04.tar.gz) | v0.4.0-rc2 | July 9, 2019 |
 | [Ubuntu 18.04 (CUDA 10.0)](https://storage.googleapis.com/swift-tensorflow-artifacts/releases/v0.4/rc2/swift-tensorflow-RELEASE-0.4-cuda10.0-cudnn7-ubuntu18.04.tar.gz) | v0.4.0-rc2 | July 9, 2019 |
 | [Ubuntu 18.04 (CUDA 9.2)](https://storage.googleapis.com/swift-tensorflow-artifacts/releases/v0.4/rc2/swift-tensorflow-RELEASE-0.4-cuda9.2-cudnn7-ubuntu18.04.tar.gz) | v0.4.0-rc2 | July 9, 2019 |
 
-<details>
-  <summary>Older Packages</summary>
-
 | Download | Version | Date |
 |----------|---------|------|
 | [Xcode 11 beta](https://storage.googleapis.com/swift-tensorflow-artifacts/releases/v0.4/rc0/swift-tensorflow-RELEASE-0.4-osx.pkg) | v0.4.0-rc0 | June 27, 2019 |