Re-implement Statement::apply in terms of Visitor
Move Statement::inlineScan into inline.c
Move Expression::inlineScan into inline.c
Move Dsymbol::inlineScan into inline.c
Merge pull request #3111 from yebblies/sapplyvisitor

[DDMD] [refactor] Re-implement Statement::apply in terms of Visitor
Merge pull request #3164 from yebblies/inlinescan

[DDMD] [refactor] Move inlineScan into a visitor class in inline.c
Move buildArrayIdent into a visitor class
Move buildArrayLoop into a visitor class
Convert array op utility functions into free functions
Merge pull request #3185 from yebblies/arrayop

[DDMD] [refactor] Move arrayop functions into visitor classes in arrayop.c
Move Expression::apply into a visitor class
Move lambdaInlineCost to use the apply visitor
Move lambdaSetParent and lambdaCheckForNestedRef to use the apply visitor
Move hasSideEffect to use the apply visitor
Fixes Issue 11823 - Ddoc symbol with a double underscore prefix should be specially parsed.
Merge pull request #3180 from AndrejMitrovic/Fix11823

Issue 11823 - Ddoc symbol with a double underscore prefix should be specially parsed.
Merge pull request #3186 from yebblies/apply

[DDMD] [refactor] Move Expression::apply into a visitor class
Remove some comments inside expressions
Remove empty statement
Explicitly compare with zero