Prepare migrating testing auxiliary functions from tests
to testutil.
Remove local duplicates on testutil.WriteToNewTempFile().
Always favor testutil.NewTestCaseDir() over ioutil.TempDir().
Add test cases for the testing auxiliary functions.
crypto/keyring:
`Keybase` interface gives way to its successor: `Keyring`. `LegacyKeybase`
interface is added in order to guarantee limited backward compatibility with
the old `Keybase` interface for the sole purpose of migrating keys across
the new keyring backends.
The package no longer depends on the `github.com/types.Config`
singleton.
`SupportedAlgos` and `SupportedLedgerAlgos` methods have been removed.
The keyring just fails when trying to perform an action with an unsupported
algorithm.
crypto/ subdirs reorganization:
`crypto/keys/hd` was moved to `crypto/hd`, which now groups together
all HD wallets related types and utilities.
client/input:
* Removal of unnecessary `GetCheckPassword`, `PrintPrefixed` functions.
* `GetConfirmation`'s signature changed to take in a io.Writer for better integration
with `cobra.Command` types.
client/context:
* In-memory keyring is allocated in the context when `--gen-only` flag is passed
in. `GetFromFields` does no longer silently allocate a keyring, it takes one as
argument.
Co-authored with @jgimeno
Co-authored-by: Jonathan Gimeno <jgimeno@gmail.com>
Alessio Treglia