Downgrade to golang 1.11.5 as there is a major bug with crypto/x509 w…

…hen building darwin binaries

See golang/go#30763 for details.

Dockerfile

@@ -1,4 +1,4 @@
-FROM golang:1.12.0-alpine
+FROM golang:1.11.5-alpine
 MAINTAINER GoCD Team <[email protected]>
 
 RUN apk add --no-cache \

README.md

@@ -3,9 +3,10 @@ A docker image containing a Golang environment for builds
 
 ## Includes everything needed to build a basic golang project
 
-- golang 1.12.0
+- golang 1.11.5
 - git
 - gcc
+- musl-dev (lib c headers, etc.)
 - bash
 
 ## And some some extra utils that are useful:
@@ -16,5 +17,12 @@ A docker image containing a Golang environment for builds
 ## Building the image locally
 
 ```
-docker build . -t gocddev/golang-build:1.12.0-alpine -f Dockerfile
+docker build . -t gocddev/golang-build:1.11.5-alpine -f Dockerfile
+```
+
+## Running
+
+```
+# starts bash session, `-v` mounts a host path to container mount point
+docker run -it -v /host/path:/path/to/mount/point gocddev/golang-build:1.11.5-alpine /bin/bash
 ```