codecov.yml: Remove the file. We used it to exclude code coverage stats for md2html, but there's no reason to do so anymore.
diff --git a/codecov.yml b/codecov.yml
deleted file mode 100644
index 9cb19ea..0000000
--- a/codecov.yml
+++ /dev/null
@@ -1,4 +0,0 @@
-# YAML definition for codecov.io code coverage reports.
-
-ignore:
- - "md2html"