Small fixes (#42)

* UI color fixes
* Typos
* Fancy badge in README

README.md

@@ -3,6 +3,7 @@
 ![GitHub release (latest SemVer)](https://img.shields.io/github/v/release/thomiceli/opengist?sort=semver)
 ![License](https://img.shields.io/github/license/thomiceli/opengist?color=blue)
 ![GitHub Workflow Status](https://img.shields.io/github/actions/workflow/status/thomiceli/opengist/go.yml)
+[![Go Report Card](https://goreportcard.com/badge/github.com/thomiceli/opengist)](https://goreportcard.com/report/github.com/thomiceli/opengist)
 
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