Replace all usages of the "github.com/go-errors/errors" and
"github.com/pkg/errors" packages with the standard lib's "errors"
package. This ensures that error wrapping and `errors.Is` checks will
work as expected.
This commit contains a series of post-merge fixes which include:
* ToBytes -> Encode
* As the former version doesn’t _require_ allocation of new slices *
* Store -> AddNextEntry
* To communicate to the caller that entries MUST be added
in order
* Several grammar, spacing, spelling and gofmt fixes.
