Update docs, removing brew --devel

docs/development/homebrew.md

@@ -5,20 +5,20 @@ Homebrew makes installing kops [very simple for MacOS.](../install.md)
 brew update && brew install kops
 ```
 
-Development Releases and master can also be installed via Homebrew very easily:
+Master can also be installed via Homebrew very easily:
 ```bash
-# Development Release
-brew update && brew install kops --devel
 # HEAD of master
 brew update && brew install kops --HEAD
 ```
 
+Previously we could also ship development updates to homebrew but their [policy has changed.](https://github.com/Homebrew/brew/pull/5060#issuecomment-428149176)
+
 Note: if you already have kops installed, you need to substitute `upgrade` for `install`.
 
-You can switch between development and stable releases with:
+You can switch between installed releases with:
 ```bash
-brew switch kops 1.7.1
-brew switch kops 1.8.0-beta.1
+brew switch kops 1.9.0
+brew switch kops 1.10.0
 ```
 
 # Releasing kops to Brew
@@ -31,20 +31,11 @@ Submitting a new release of kops to Homebrew is very simple.
 This will automatically update the provided fields and open a PR for you.
 More details on this script are located [here.](https://github.com/Homebrew/brew/blob/master/Library/Homebrew/dev-cmd/bump-formula-pr.rb)
 
-We now include both major and development releases in homebrew.  A development version can be updated by adding the `--devel` flag.
-
 Example usage:
 ```bash
-# Major Version
 brew bump-formula-pr kops \
        --url=https://github.com/kubernetes/kops/archive/1.7.1.tar.gz \
        --sha256=044c5c7a737ed3acf53517e64bb27d3da8f7517d2914df89efeeaf84bc8a722a
-
-# Development Version
-brew bump-formula-pr kops \
-       --devel \
-       --url=https://github.com/kubernetes/kops/archive/1.8.0-beta.1.tar.gz \
-       --sha256=81026d6c1cd7b3898a88275538a7842b4bd8387775937e0528ccb7b83948abf1
 ```
 
 * Update the URL variable to the tar.gz of the new release source code