Seeds math/rand in main() for the "memoryless" package (#14)

* Seeds math/rand before calling memoryless package

https://pkg.go.dev/math/rand#Seed

* Reinstalls ca-certificates before building anything

* Runs apt-get using sudo

* Uses Focal as dist for Travis, and does apt-get update

* Moves apt install to before_script section

* Updates to Go 1.16 + uses Travis apt addon

* Sets waittime to 3s for unit test of main()

* Updates Go to 1.16 in Docker image

Also, reinstalls ca-certificates package.

* Sets GO111MODULE=auto in Docker build

* Adds comment about rand.Seed() is being called.

* Enables Go modules.

Author: nkinkade

.travis.yml

@@ -1,5 +1,15 @@
+dist: focal
+
 language: go
 
+go:
+- 1.16
+
+addons:
+  apt:
+    update: true
+    packages: ca-certificates
+
 before_script:
 - go get golang.org/x/tools/cmd/cover
 - go get github.com/mattn/goveralls

Dockerfile

@@ -1,7 +1,8 @@
-FROM golang:1.12 as build
+FROM golang:1.16 as build
 ENV CGO_ENABLED 0
 COPY . /go/src/github.com/m-lab/nodeinfo
 WORKDIR /go/src/github.com/m-lab/nodeinfo
+RUN apt update && apt reinstall ca-certificates
 RUN go get \
     -v \
     -ldflags "-X github.com/m-lab/go/prometheusx.GitShortCommit=$(git log -1 --format=%h)" \

go.mod

@@ -0,0 +1,9 @@
+module github.com/m-lab/nodeinfo
+
+go 1.16
+
+require (
+	github.com/m-lab/go v0.1.45
+	github.com/prometheus/client_golang v1.11.0
+	gopkg.in/m-lab/pipe.v3 v3.0.0-20180108231244-604e84f43ee0
+)