add PyPI version badge to the README

Add a shields.io badge showing the latest ARver version at PyPI.

Also, change the downloads badge from pepy.tech to shields.io. The
appearance of the badges is consistent, and the font kerning is better
in the shields.io badge.

Author: arcctgx

README.md

@@ -1,7 +1,8 @@
 # ARver
 
 [![Unit tests](https://github.com/arcctgx/ARver/actions/workflows/unit-tests.yml/badge.svg)](https://github.com/arcctgx/ARver/actions/workflows/unit-tests.yml)
-[![Downloads](https://static.pepy.tech/badge/arver)](https://pepy.tech/project/arver)
+[![PyPI version](https://img.shields.io/pypi/v/ARver?logo=python&label=PyPI)](https://pypi.org/project/ARver/)
+[![PePy downloads](https://img.shields.io/pepy/dt/ARver?logo=python&label=Downloads&color=%230C7DBE)](https://pepy.tech/project/ARver)
 
 `ARver` is a command-line program for verifying audio tracks ripped from a CD
 against checksums stored in AccurateRip database.