[#62] client: move package from neofs-api-go

Signed-off-by: Evgenii Stratonikov <evgeniy@nspcc.ru>

client/client.go

@@ -0,0 +1,45 @@
+package client
+
+import (
+	"io"
+
+	"github.com/nspcc-dev/neofs-api-go/rpc/client"
+)
+
+// Client represents NeoFS client.
+type Client interface {
+	Accounting
+	Container
+	Netmap
+	Object
+	Session
+	Reputation
+
+	// Raw must return underlying raw protobuf client.
+	Raw() *client.Client
+
+	// Conn must return underlying connection.
+	//
+	// Must return a non-nil result after the first RPC call
+	// completed without a connection error.
+	Conn() io.Closer
+}
+
+type clientImpl struct {
+	raw *client.Client
+
+	opts *clientOptions
+}
+
+func New(opts ...Option) (Client, error) {
+	clientOptions := defaultClientOptions()
+
+	for i := range opts {
+		opts[i](clientOptions)
+	}
+
+	return &clientImpl{
+		opts: clientOptions,
+		raw:  client.New(clientOptions.rawOpts...),
+	}, nil
+}