Split docker file up to improve cacheability

Run hooks/pre-commit on build

Use /bin/sh rather than /bin/bash for hooks/pre-commit

.dockerignore

@@ -1,6 +1,5 @@
 vendor/pkg
 vendor/src
 pkg
-hooks
 bin
 .git

Dockerfile

@@ -1,13 +1,16 @@
 # Build go-neb
 FROM golang:1.10-alpine as builder
+RUN apk add --no-cache -t build-deps git gcc musl-dev go
 
 COPY . /tmp/go-neb
 WORKDIR /tmp/go-neb
-RUN apk add --no-cache -t build-deps git gcc musl-dev go \
-    && go get -u github.com/constabulary/gb/... \
+RUN go get -u github.com/constabulary/gb/... \
+    && go get github.com/golang/lint/golint \
+    && go get github.com/fzipp/gocyclo \
     && gb vendor restore \
     && gb build -f github.com/matrix-org/go-neb
 
+RUN /tmp/go-neb/hooks/pre-commit
 
 # Run go-neb
 FROM alpine:3.7

hooks/pre-commit

@@ -1,4 +1,4 @@
-#! /bin/bash
+#!/bin/sh
 
 set -eu