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/libpod/image/image.go b/libpod/image/image.go
index f5bf47694..0900944eb 100644
--- a/libpod/image/image.go
+++ b/libpod/image/image.go
@@ -867,7 +867,7 @@ func (i *Image) PushImageToReference(ctx context.Context, dest types.ImageRefere
 	// Copy the image to the remote destination
 	manifestBytes, err := cp.Image(ctx, policyContext, dest, src, copyOptions)
 	if err != nil {
-		return errors.Wrapf(err, "Error copying image to the remote destination")
+		return errors.Wrapf(err, "error copying image to the remote destination")
 	}
 	digest, err := manifest.Digest(manifestBytes)
 	if err != nil {