Editor code: tidy up BOOLs,NULLs and overrides pt1.

A few 'typedefs' replaced by 'using's
This shouldn't have any functional changes at all, just c++17 modernization
It's a part 1 of a split #2847

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

Code/Editor/Controls/ConsoleSCB.cpp

@@ -62,14 +62,14 @@ public:
     }
 
 protected:
-    void highlightBlock(const QString &text)
+    void highlightBlock(const QString &text) override
     {
         auto pos = -1;
         QTextCharFormat myClassFormat;
         myClassFormat.setFontWeight(QFont::Bold);
         myClassFormat.setBackground(Qt::yellow);
 
-        while (1)
+        while (true)
         {
             pos = text.indexOf(m_searchTerm, pos+1, Qt::CaseInsensitive);
 
@@ -567,7 +567,7 @@ static CVarBlock* VarBlockFromConsoleVars()
     size_t cmdCount = console->GetSortedVars(&cmds[0], cmds.size());
 
     CVarBlock* vb = new CVarBlock;
-    IVariable* pVariable = 0;
+    IVariable* pVariable = nullptr;
     for (int i = 0; i < cmdCount; i++)
     {
         ICVar* pCVar = console->GetCVar(cmds[i]);