Add readme

README.md

+# Project Title
+
+## Table of Contents
+
+- [About](#about)
+- [Getting Started](#getting_started)
+- [Usage](#usage)
+
+## About <a name = "about"></a>
+
+This CLI utility can be used for generating a GC access token with no need to install any Google SDKs or dependencies.
+
+## Getting Started <a name = "getting_started"></a>
+The project has the compiled utility for x86_64 Linux only. However, if there is a need for the CLI for other OS or architecture, it is possible to compile it from the source. 
+
+### Compile
+
+```zsh
+git clone git@community.opengroup.org:osdu/platform/deployment-and-operations/base-containers-gcp/gc-auth-credentials.git
+
+go build -ldflags "-s -w" 
+```
+
+## Usage <a name = "usage"></a>
+
+### How to use it on x86_64 Linux.
+
+```zsh
+curl https://community.opengroup.org/projects/1410/packages/generic/gc_auth_token/master/gc_auth_token -o gc_auth_token
+
+chmod +x gc_auth_token
+
+export GOOGLE_APPLICATION_CREDENTIALS=<path-to-the-sa-key-json>
+
+./gc_auth_token  # will print access token
+```
+
+More info about `GOOGLE_APPLICATION_CREDENTIALS` could be found here: https://cloud.google.com/docs/authentication/application-default-credentials#GAC.
+