Add logo
fixes:
+![TopoLVM logo](./docs/img/TopoLVM_logo.svg)
[![GitHub release](https://img.shields.io/github/v/release/topolvm/topolvm.svg?maxAge=60)][releases]
[![Main](https://github.com/topolvm/topolvm/workflows/Main/badge.svg)](https://github.com/topolvm/topolvm/actions)
[![PkgGoDev](https://pkg.go.dev/badge/github.com/topolvm/topolvm?tab=overview)](https://pkg.go.dev/github.com/topolvm/topolvm?tab=overview)
