message: update README: add installation, build instruction
diff: ## Installation
  -Download latest Kubeapps Installer from the [release page](https://github.com/kubeapps/installer/releases)
  +Installation is made of two steps:
  -## Build
  +- Download latest Kubeapps Installer binary from the [release page](https://github.com/kubeapps/installer/releases). Currently Kubeapps Installer is distributed in two platforms: linux/amd64 and OSX/amd64
  +- Make the binary executable
  +## Build from source
  +
  +You can build latest Kubeapps Installer from source.
  +
  +### Installing Go
  +- Visit https://golang.org/dl/
  +- Download the most recent Go version (here we used 1.9) and unpack the file
  +- Check the installation process on https://golang.org/doc/install
  +- Set the Go environment variables
  +
  +```
  +$ export GOROOT=/GoDir/go
  +$ export GOPATH=/GoDir/go
  +$ export PATH=$GOPATH/bin:$PATH
  +```
  +
  +### Create a working directory for the project
  +```
  +$ working_dir=$GOPATH/src/github.com/kubeapps/
  +$ mkdir -p $working_dir
  +```
  +
  +### Clone kubeapps/installer repository
  +```
  +$ cd $working_dir
  +$ git clone https://github.com/kubeapps/installer
  +```
  +
  +### Building local binary
  ```
  +$ cd installer
  $ make binary
  ```
  -## Usage
  +## Testing Kubeapps Installer with minikube
  +
  +The simplest way to try Kubeapps is deploying it with Kubeapps Installer on [minikube](https://github.com/kubernetes/minikube).
  +
  +Kubeapps Installer is now working with RBAC-enabled Kubernetes (v1.7+). You can choose to start minikube vm with your preferred VM driver (virtualbox xhyve vmwarefusion) and a proper Kubernetes version. For example, the [latest minikube](https://github.com/kubernetes/minikube/releases/tag/v0.23.0) will start a Kubernetes v1.8.0.
  +
  +```
  +$ minikube start
  +```
  +
  +It's also required to have [Kubectl](https://kubernetes.io/docs/tasks/tools/install-kubectl/) installed on your machine. Verify Kubernetes version:
  ```
  -# Bring up cluster
  -$ ./kubeapps up
  +$ kubectl version
  +Client Version: version.Info{Major:"1", Minor:"7", GitVersion:"v1.7.0", GitCommit:"d3ada0119e776222f11ec7945e6d860061339aad", GitTreeState:"clean", BuildDate:"2017-06-29T23:15:59Z", GoVersion:"go1.8.3", Compiler:"gc", Platform:"darwin/amd64"}
  +Server Version: version.Info{Major:"1", Minor:"8", GitVersion:"v1.8.0", GitCommit:"0b9efaeb34a2fc51ff8e4d34ad9bc6375459c4a4", GitTreeState:"dirty", BuildDate:"2017-10-17T15:09:55Z", GoVersion:"go1.8.3", Compiler:"gc", Platform:"linux/amd64"}
  +```
  +
  +Deploy Kubeapps with Kubeapps Installer
  -# Bring down cluster
  -$ ./kubeapps down
  +```
  +$ kubeapps up
  ```
  +Remove Kubeapps
  +
  +```
  +$ kubeapps down
  +```
  \ No newline at end of file
  