Introduce constants for Tarantool field types

[akudiyar]

Currently, there are no defined constants for Tarantool field types in space metadata. It causes duplicated code in the derived modules (e.g. tarantool-spark).

I suggest adding such constants and use an enum for the field type value. The list of types must be taken from the official doc: https://www.tarantool.io/en/doc/latest/reference/reference_lua/box_space/format/