Cleanup SQL types

[kyukhin]

Tarantool version: 2.1

OS version: any

Bug description:

SQL type system of Tarantool 2.1 should be more or less consistent.

Let's do some cleanup:

1. Remove DATE/TIME/DATETIME from prarser
2. Remove CHAR from parser
3. Remove DECIMAL/NUMERIC/NUM from parser

So, at the end of the day following types should be supported by SQL:

1. TEXT/VARCHAR(N), N is ignored, represented as STRING in space format
2. INTEGER/INT, represented as INTEGER in space format
3. FLOAT/REAL/DOUBLE, represented as NUMBER in space format (subject to change in future)
4. [biggest part of the issue] Suppoty new type BLOB, represented as BINARY in format.
   There's no such a type in formats, so need to introduce new field type and patch whole
   Tarantool thoroughly

[Totktonada]

See #3650 re BLOBs.

[Korablev77]

Last point

4. [biggest part of the issue] Suppoty new type BLOB, represented as BINARY in format.
There's no such a type in formats, so need to introduce new field type and patch whole
Tarantool thoroughly

now is blocked by #4023