* feat(optimizer): MCOL-5250 rewrite queries with DISTINCT
... as aggregated queries.
So query
```
SELECT DISTINCT <cols list>
FROM <from list>
WHERE <where clause>
HAVING <having clause>
ORDER BY <orderby list>
LIMIT <limit>
```
will become
```
SELECT *
FROM
(
SELECT <cols list>
FROM <from list>
WHERE <where clause>
HAVING <having clause>
) a
GROUP BY 1,2,3,...,N
ORDER BY <orderby list>
LIMIT limit
```
* move ORDER BY to the outer query
* fix test
* reuse cloneWORecursiveSelects() in clone()
* fix subselect columns processing
* toCppCode for ParseTree and TreeNode
* generated tree is compiling
* Put tree constructors into tests
* Minor fixes
* Fixed parse + some constructors
* Fixed includes, removed debug and old data
* Hopefully fix clang errors
* Forgot an override
* More overrides
