Add support to change the number of lines of the compile output

This patch adds support to modify the number of line shown in the
compile output window. This will allow users with big projects to have
more room to look at when compiling.

Task-number: QTCREATORBUG-2200
Change-Id: I1023b2150a3eff4a33b8872fb711d150e5a8b00c
Reviewed-by: Eike Ziller <eike.ziller@qt.io>

src/plugins/coreplugin/coreconstants.h

@@ -208,6 +208,7 @@ const char TR_CLEAR_MENU[]         = QT_TRANSLATE_NOOP("Core", "Clear Menu");
 const char DEFAULT_BUILD_DIRECTORY[] = "../%{JS: Util.asciify(\"build-%{CurrentProject:Name}-%{CurrentKit:FileSystemName}-%{CurrentBuild:Name}\")}";
 
 const int TARGET_ICON_SIZE = 32;
+const int DEFAULT_MAX_LINE_COUNT = 100000;
 
 } // namespace Constants
 } // namespace Core