Add badge for number of lines and files

Author: gkobeaga

README.md

@@ -3,6 +3,8 @@
 
 [![Actions Status](https://github.com/gkobeaga/op-solver/workflows/Build-Heur/badge.svg)](https://github.com/gkobeaga/op-solver/actions)
 [![Actions Status](https://github.com/gkobeaga/op-solver/workflows/Build-Exact/badge.svg)](https://github.com/gkobeaga/op-solver/actions)
+[![Lines](https://tokei.rs/b1/github/gkobeaga/op-solver)](https://github.com/XAMPPRocky/tokei)
+[![Files](https://tokei.rs/b1/github/gkobeaga/op-solver?category=files)](https://github.com/XAMPPRocky/tokei)
 [![License](https://img.shields.io/badge/License-Apache%202.0-blue.svg)](https://github.com/gkobeaga/op-solver/blob/master/LICENSE)
 
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