Why three readme files in the git repo?

[petterreinholdtsen]

In the git repository there are three readme files: Readme.md README.md README.txt

Would it be enough with one readme file?

[rdoeffinger]

+1 from me, it is confusing. From what I can tell, the Readme.md is the most up-to-date one, with the others being outdated.
Unfortunately, github shows the README.md by default instead...