Editor code: tidy up BOOLs,NULLs and overrides pt5. (#2876)

A few 'typedefs' replaced by 'using's
This shouldn't have any functional changes at all, just c++17 modernization
It's a part 5 of a split #2847

Signed-off-by: Nemerle <nemerle5+git@gmail.com>

Co-authored-by: Nemerle <nemerle5+git@gmail.com>

Code/Editor/CrtDebug.cpp

@@ -62,7 +62,7 @@ int crtAllocHook(int nAllocType, void* pvData,
 {
     if (nBlockUse == _CRT_BLOCK)
     {
-        return(TRUE);
+        return TRUE;
     }
 
     static int total_cnt = 0;