add logo (#150)

README.md

@@ -1,13 +1,18 @@
-# Categraf
+## Categraf
+
+<a href="https://github.com/flashcatcloud/categraf">
+  <img src="doc/categraf.png" alt="categraf, one-stop telemetry collector" width="80" />
+</a>
+
 [![Powered By Flashcat](https://img.shields.io/badge/Powered%20By-Flashcat-blueviolet)](https://flashcat.cloud/)
 [![Release](https://img.shields.io/github/v/release/flashcatcloud/categraf)](https://github.com/flashcatcloud/categraf/releases/latest)
 [![Docker pulls](https://img.shields.io/docker/pulls/flashcatcloud/categraf)](https://hub.docker.com/r/flashcatcloud/categraf/)
 [![Starts](https://img.shields.io/github/stars/flashcatcloud/categraf)](https://github.com/flashcatcloud/categraf/stargazers)
 [![Forks](https://img.shields.io/github/forks/flashcatcloud/categraf)](https://github.com/flashcatcloud/categraf/fork)
 [![Contributors](https://img.shields.io/github/contributors-anon/flashcatcloud/categraf)](https://github.com/flashcatcloud/categraf/graphs/contributors)
-[!["License"](https://img.shields.io/badge/license-MIT-red)](https://github.com/flashcatcloud/categraf/blob/main/LICENSE)
+[!["License"](https://img.shields.io/badge/license-MIT-blue)](https://github.com/flashcatcloud/categraf/blob/main/LICENSE)
 
-Categraf is a monitoring agent for nightingale / prometheus / m3db / victoriametrics / thanos / influxdb / tdengine.
+Categraf is one-stop telemetry collector for nightingale / prometheus / m3db / victoriametrics / thanos / influxdb / tdengine.
 
 
 ## Links