Assumes README.md is always all caps

[tollmanz]

When a repo's README is lowercase (i.e., readme.md), Archbot will add a capitalized version of the file README.md when adding the badge. This causes issues when an OS X user checks out the repo due to Git being case insensitive on OS X. Git will checkout readme.md, then overwriting it with README.md. Mass confusion ensues!

Expected Behavior

Archbot should not change the case of the README file when adding the badge.

Current Behavior

Archbot will always save the README file as README.md.

Possible Solution

Determine the exact spelling of the README file and use it as the value when saving the README back to the repo.

Steps to Reproduce (for bugs)

1. Create a new repo with readme.md and some content
2. Have Archbot add a badge
3. Notice both a README.md and readme.md file in the repo
4. Clone the repo and notice the confusing git status

Context

After checking out Wren, it showed issues with the README file (https://github.com/CondeNast/wren). You can see that the problem was created here: https://github.com/CondeNast/wren/commit/3e0ff648d58b420871abbadf4a9a97dca5c2073c.

Your Environment

• Git repo Wren
• OS X