make target and docs (#1002)

* make target and docs

* fix grammar

Makefile

@@ -1,7 +1,12 @@
+VERSION = "unset"
+DATE=$(shell date -u +%Y-%m-%d-%H:%M:%S-%Z)
 .PHONY: build
 build:
 	cd cmd/proxy && buffalo build
 
+build-ver:
+	GO111MODULE=on CGO_ENABLED=0 go build -mod=vendor -ldflags "-X github.com/gomods/athens/pkg/build.version=$(VERSION) -X github.com/gomods/athens/pkg/build.buildDate=$(DATE)" -o athens ./cmd/proxy
+
 .PHONY: run
 run: build
 	./athens

docs/content/install/_index.md

@@ -26,7 +26,6 @@ We strongly recommend using a tagged release, e.g. `gomods/athens:v0.2.0`, inste
 
 To make sure it's easy to install, we try to provide as many ways as possible to install and run Athens:
 
-- It's written in Go, so we provide a self-contained binary. You can configure and run the binary on your machine(s)
-    - Instructions on how to run directly from the binary are coming soon
+- It's written in Go, so you can easily build it yourself on almost any platform. You can also build the binary providing your own version and build time. See [here](./build-from-source)
 - We provide a [Docker image](https://hub.docker.com/r/gomods/athens/) and [instructions on how to run it](./shared-team-instance)
 - We provide [Kubernetes](https://kubernetes.io) [Helm Charts](https://helm.sh) with [instructions on how to run Athens on Kubernetes](./install-on-kubernetes)

docs/content/install/build-from-source.md

@@ -0,0 +1,34 @@
+---
+title: Building a versioned Athens binary from source
+description: Building a versioned Athens binary from source
+weight: 1
+---
+You can do that easily with just few commands:
+
+**Bash**
+```bash
+git clone https://github.com/gomods/athens
+cd athens
+make build-ver VERSION="0.2.0"
+```
+
+**PowerShell**
+```PowerShell
+git clone https://github.com/gomods/athens
+cd athens
+$env:GO111MODULE="on"
+$version = "0.2.0"
+$date = (Get-Date).ToUniversalTime()
+go build -mod=vendor -ldflags "-X github.com/gomods/athens/pkg/build.version=$version -X github.com/gomods/athens/pkg/build.buildDate=$date" -o athens ./cmd/proxy
+```
+
+This will give you a binary named `athens`. You can print the version and time information by running:
+```console
+ ./athens -version
+```
+which should return something like:
+```console
+Build Details:
+        Version:        0.2.0
+        Date:           2018-12-13-20:51:06-UTC
+```