NotifyError to sentry.

NotifyErrorOnce will send an error if it has never occurred in this current process.

NotifyIfPanic recovers from the panic and sends the error to Sentry, panicking shortly thereafter.

Setup sentry global scope, and add some initial context tags: environment and application name.

Exported functions from sentry's original package to avoid importing it.

Exported functions from sentry's original package to avoid importing it.

Hasher transforms the object into an unique hash string.

Typeable interface is used to define a type for the error, to show in Sentry instead of the usual fmt.Wrap or errors.withStack.