Debugger: Rework display length limitation systems

There are two values now, one to limit an entry in the L&E view
(default 100) and a hard upper limit (at 1 mio).

If displayed values are elided, the true length is shown in addition.

Change-Id: I180b70446c18e258c164e5af75b88d4c8b6c53f2
Reviewed-by: hjk <hjk121@nokiamail.com>

src/plugins/debugger/gdb/gdbengine.cpp

@@ -4841,7 +4841,10 @@ void GdbEngine::updateLocalsPython(const UpdateParameters &params)
     expanded += "formats:" + handler->individualFormatRequests();
 
     QByteArray cutOff = " stringcutoff:"
-        + debuggerCore()->action(MaximalStringLength)->value().toByteArray();
+        + debuggerCore()->action(MaximalStringLength)->value().toByteArray()
+        + " displaystringlimit:"
+        + debuggerCore()->action(DisplayStringLimit)->value().toByteArray();
+
 
     QByteArray watchers;
     const QString fileName = stackHandler()->currentFrame().file;