builder: follow redirects for gopkg.in
builder: follow redirects for gopkg.in

Resolves errors:

    bash-4.3$ go get -d ./...
    # cd .; git clone https://gopkg.in/square/go-jose.v1 /home/developer/src/gopkg.in/square/go-jose.v1
    Cloning into '/home/developer/src/gopkg.in/square/go-jose.v1'...
    error: RPC failed; HTTP 301 curl 22 The requested URL returned error: 301
    fatal: The remote end hung up unexpectedly
    package gopkg.in/square/go-jose.v1: exit status 128
    # cd .; git clone https://gopkg.in/natefinch/lumberjack.v2 /home/developer/src/gopkg.in/natefinch/lumberjack.v2
    Cloning into '/home/developer/src/gopkg.in/natefinch/lumberjack.v2'...
    error: RPC failed; HTTP 301 curl 22 The requested URL returned error: 301
    fatal: The remote end hung up unexpectedly
    package gopkg.in/natefinch/lumberjack.v2: exit status 128
    # cd .; git clone https://gopkg.in/yaml.v2 /home/developer/src/gopkg.in/yaml.v2
    Cloning into '/home/developer/src/gopkg.in/yaml.v2'...
    error: RPC failed; HTTP 301 curl 22 The requested URL returned error: 301
    fatal: The remote end hung up unexpectedly
    package gopkg.in/yaml.v2: exit status 128

jumanjihouse/docker-caddy,jumanjiman/docker-caddy