move QT+=network to projectexplorer_dependencies.pri

it's used in both the plugin itself and in the plugin's .pri

Change-Id: Ifeea9660270638dd2eb3d42d9784364e7c60b233
Reviewed-by: Eike Ziller <eike.ziller@digia.com>
Reviewed-by: Tobias Hunger <tobias.hunger@digia.com>

src/plugins/projectexplorer/projectexplorer.pri

 include(projectexplorer_dependencies.pri)
 LIBS *= -l$$qtLibraryName(ProjectExplorer)
-QT *= network

src/plugins/projectexplorer/projectexplorer.pro

 TEMPLATE = lib
 TARGET = ProjectExplorer
-QT += xml script network declarative
+QT += xml script declarative
 
 include(../../qtcreatorplugin.pri)
 include(projectexplorer_dependencies.pri)

src/plugins/projectexplorer/projectexplorer_dependencies.pri

@@ -3,3 +3,4 @@ include(../../plugins/locator/locator.pri)
 include(../../plugins/find/find.pri)
 include(../../plugins/coreplugin/coreplugin.pri)
 include(../../plugins/texteditor/texteditor.pri)
+QT *= network