sql: introduce field type ANY

Closes #3174

@TarantoolBot document
Title: Field type ANY in SQL

Properties of type ANY in SQL:
1) typeof() with an argument of type ANY returns "any";
2) any value of any type can be implicitly and explicitly cast to the ANY type;
3) a value of type ANY cannot be implicitly cast to any other type;
4) a value of type ANY cannot participate in arithmetic, bitwise, comparison,
   and concationation operations.