Bump to go 1.13.8 and flatbuffers 1.11.0 in build image

The "build image" is a docker image used for building the jk binary
(on Linux, anyway). This commit updates the version of go (to 1.13.8)
and the version of flatbuffers (1.11.0) included in the image.

It also renames the miage to jkcfg/build, which is shorter and more
on-brand.

Makefile

@@ -37,7 +37,7 @@ install: jk
 	cp jk $(D)
 
 build-image:
-	docker build -t quay.io/justkidding/build -f build/Dockerfile build/
+	docker build -t jkcfg/build -f build/Dockerfile build/
 
 # Pulls the std/node_modules directory
 std-install:

build/Dockerfile

@@ -1,5 +1,5 @@
 # Build v8
-FROM golang:1.12.1 as v8builder
+FROM golang:1.13.8 as v8builder
 RUN apt-get update && apt-get install -y \
     bzip2 \
     libglib2.0-dev \
@@ -11,11 +11,11 @@ RUN cd $GOPATH/src/github.com/jkcfg/v8worker2 \
     && ./build.py
 
 # Build flatbuffer compiler, flatc
-FROM golang:1.12.1 as flatc-builder
+FROM golang:1.13.8 as flatc-builder
 RUN apt-get update && apt-get install -y \
     cmake \
   && rm -rf /var/lib/apt/lists/*
-ENV FLATBUFFERS_VERSION 1.10.0
+ENV FLATBUFFERS_VERSION 1.11.0
 RUN curl -fsSLO --compressed "https://github.com/google/flatbuffers/archive/v${FLATBUFFERS_VERSION}.tar.gz" \
     && tar -xf v${FLATBUFFERS_VERSION}.tar.gz \
     && rm v${FLATBUFFERS_VERSION}.tar.gz \
@@ -27,12 +27,12 @@ RUN curl -fsSLO --compressed "https://github.com/google/flatbuffers/archive/v${F
     && rm -rf flatbuffers-${FLATBUFFERS_VERSION}
 
 # Build github-release
-FROM golang:1.12.1 as github-release-builder
+FROM golang:1.13.8 as github-release-builder
 RUN go get github.com/aktau/github-release \
   && cp `go env GOPATH`/bin/github-release /usr/local/bin \
   && rm -rf `go env GOPATH`/src/github.com/aktau/github-release
 
-FROM golang:1.12.1 as fetcher
+FROM golang:1.13.8 as fetcher
 RUN apt-get update && apt-get install -y \
     xz-utils \
   && rm -rf /var/lib/apt/lists/*
@@ -56,7 +56,7 @@ RUN curl -fsSLo /usr/local/bin/gosu "https://github.com/tianon/gosu/releases/dow
     && chmod +x /usr/local/bin/gosu
 
 # Our final build image
-FROM golang:1.12.1
+FROM golang:1.13.8
 COPY --from=v8builder /go/src/github.com/jkcfg/v8worker2/v8.pc /usr/local/lib/pkgconfig/
 RUN sed -i \
      -e 's#Cflags: .*#Cflags: -I/usr/local/include/v8#' \

run-in-docker.sh

@@ -1,4 +1,4 @@
 #!/bin/bash
 
 pkg=github.com/jkcfg/jk
-docker run -v "$(pwd)":/go/src/$pkg quay.io/justkidding/build "$@"
+docker run -v "$(pwd)":/go/src/$pkg jkcfg/build "$@"