Lowercase some errors

This commit is courtesy of

```
for f in $(git ls-files *.go | grep -v ^vendor/); do \
	sed -i 's/\(errors\..*\)"Error /\1"error /' $f;
done

for f in $(git ls-files *.go | grep -v ^vendor/); do \
	sed -i 's/\(errors\..*\)"Failed to /\1"failed to /' $f;
done

```

etc.

Self-reviewed using `git diff --word-diff`, found no issues.

Signed-off-by: Kir Kolyshkin <kolyshkin@gmail.com>

1 files changed, 1 insertions, 1 deletions

diff --git a/pkg/api/handlers/libpod/play.go b/pkg/api/handlers/libpod/play.go
index 2296e170a..b81bc9d6b 100644
--- a/pkg/api/handlers/libpod/play.go
+++ b/pkg/api/handlers/libpod/play.go
@@ -50,7 +50,7 @@ func PlayKube(w http.ResponseWriter, r *http.Request) {
 	}
 	authConf, authfile, key, err := auth.GetCredentials(r)
 	if err != nil {
-		utils.Error(w, "Failed to retrieve repository credentials", http.StatusBadRequest, errors.Wrapf(err, "Failed to parse %q header for %s", key, r.URL.String()))
+		utils.Error(w, "failed to retrieve repository credentials", http.StatusBadRequest, errors.Wrapf(err, "failed to parse %q header for %s", key, r.URL.String()))
 		return
 	}
 	defer auth.RemoveAuthfile(authfile)