Refactor Parenthesed SelectBody and FromItem

[manticore-projects]

This is a heavy API breaking refactoring on the bracket-handling related to SelectBody, FromItem and OperationSet, SubSelect, WithItem:

• it fixes some issues and wrong examples (e. g. Test for Union with selects wrapped in parenthesis doesn't parse on 4.1 #1094, which was incorrect)
• simplifies the Grammar and drops some redundant productions (e. g. SubSelect, SpecialSubSelect, SubJoin, SubJoinList, SetOperationListWithoutIntialSelect, ValuesList)

It should warrant a major Version JSQLParser-5.0 and also people should properly test it before.

Goal:

• get rid of all the "hasBrackets" properties for any entity
• move JoinList from PlainSelect to FromItem (since there can't be a Join without a From)
• SelectBody replaces SubSelect and implements FromItem directly
  This has the big advantaged, that any occurrence of ( table=Table() | subSelect=SubSelect() ) can be parsed as fromItem=FromItem() without LOOKAHEAD (for example Merge parses a simple FromItem now)
• SelectBody implements Statement directly and so becomes the Select Statement (removing 1 hierarchy level from the AST):

-- before
statement = new Select().withSelectBody(new PlainSelect()
                        .addSelectItems(new AllTableColumns().withTable(t)).withFromItem(t));
statement = new Select().withSelectBody(new ValuesStatement().withExpressions(expressionList));

-- now better ( when SelectBody became Select, all its implementations became a Statement )
statement = new PlainSelect()
                        .addSelectItems(new AllTableColumns().withTable(t)).withFromItem(t);
statement = new Values().withExpressions(expressionList);

• LateralSubSelect extends ParenthesedSelectBody (axing SubSelect and SpecialSubSelect )

• values.ValuesStatement becomes select.Values implementing SelectBody (with Statement and FromItem). So we got rid of ValuesList

• move ORDER BY, LIMIT, OFFSET, FETCH, WITH isolation into SelectBody since all its implementations support it

  -- valid SQL
  values(1,2,3) limit 1
  -- valid SQL
  (values(1,2,3)) limit 1

• Nested WithItems

  with a 
      as ( with b 
             as ( with c 
                    as (select 1) 
                    select c.* from c ) 
             select b.* from b ) 
       select a.* from a

• Merge implements the Visitor Pattern

• all the Tests succeed

• verify/validate performance. It is a little bit slower but much more correct.

Before:
42500 statements parsed in 13095 milliseconds
 (3245 statements per second,  0.0003082 seconds per statement )
38500 select scans for table name executed in 80 milliseconds
 (481250 select scans for table name per second,  0.0000021 seconds per select scans for table name)

New:
42500 statements parsed in 15062 milliseconds
 (2821 statements per second,  0.0003545 seconds per statement )
38500 select scans for table name executed in 101 milliseconds
 (381188 select scans for table name per second,  0.0000026 seconds per select scans for table name)

• so far 900 lines less code at better functionality and simplicity (traversing the AST got much easier)

Fixes #1737
Fixes #1764
Succeeds on another Special Oracle Test Condition15
Succeeds on another Special Oracle Test Cast_MultiSet07

@wumpz Please start reviewing and provide feedback as early as possible.

[manticore-projects]

Can we move this forward please since it is quite a big chunk?