function toErrorMessage(error = null, verbose = false) {
    if (!error) {
        return nls.localize('error.defaultMessage', "An unknown error occurred. Please consult the log for more details.");
    }
    if (Array.isArray(error)) {
        const errors = arrays.coalesce(error);
        const msg = toErrorMessage(errors[0], verbose);
        if (errors.length > 1) {
            return nls.localize('error.moreErrors', "{0} ({1} errors in total)", msg, errors.length);
        }
        return msg;
    }
    if (types.isString(error)) {
        return error;
    }
    if (error.detail) {
        const detail = error.detail;
        if (detail.error) {
            return exceptionToErrorMessage(detail.error, verbose);
        }
        if (detail.exception) {
            return exceptionToErrorMessage(detail.exception, verbose);
        }
    }
    if (error.stack) {
        return exceptionToErrorMessage(error, verbose);
    }
    if (error.message) {
        return error.message;
    }
    return nls.localize('error.defaultMessage', "An unknown error occurred. Please consult the log for more details.");
}
Tries to generate a human readable error message out of the error. If the verbose parameter
is set to true, the error message will include stacktrace details if provided.

@returns A string containing the error message.