doc: describe tarantool submodules API

Add or update docstings for submodule files contents. Submodules are not
meant to be used directly in code, but their descriptions will be
imported automatically to core module API description. It also may
help developers of this module.

Every submodule that could be of use is indexed in documentation now.

Set sphinx autodoc module to describe members and inherited members by
default.

Dataclass with factories display is not parsed correctly, see [1] issue.

1. sphinx-doc/sphinx#10893

Part of #67

Author: DifferentialOrange

doc/api/class-connection.rst

@@ -0,0 +1,4 @@
+module :py:mod:`tarantool.connection_pool`
+==========================================
+
+.. automodule:: tarantool.connection_pool

doc/api/class-mesh-connection.rst

@@ -0,0 +1,4 @@
+module :py:mod:`tarantool.connection`
+=====================================
+
+.. automodule:: tarantool.connection

doc/api/class-response.rst

@@ -0,0 +1,4 @@
+module :py:mod:`tarantool.dbapi`
+================================
+
+.. automodule:: tarantool.dbapi

doc/api/class-space.rst

@@ -0,0 +1,4 @@
+module :py:mod:`tarantool.error`
+================================
+
+.. automodule:: tarantool.error

doc/api/submodule-connection-pool.rst

@@ -0,0 +1,4 @@
+module :py:mod:`tarantool.mesh_connection`
+==========================================
+
+.. automodule:: tarantool.mesh_connection

doc/api/submodule-connection.rst

@@ -0,0 +1,19 @@
+module :py:mod:`tarantool.msgpack_ext.types`
+============================================
+
+.. currentmodule:: tarantool.msgpack_ext.types
+
+module :py:mod:`tarantool.msgpack_ext.types.datetime`
+-----------------------------------------------------
+
+.. automodule:: tarantool.msgpack_ext.types.datetime
+   :special-members: __add__, __sub__, __eq__
+
+
+.. currentmodule:: tarantool.msgpack_ext.types
+
+module :py:mod:`tarantool.msgpack_ext.types.interval`
+-----------------------------------------------------
+
+.. automodule:: tarantool.msgpack_ext.types.interval
+   :special-members: __add__, __sub__, __eq__