core: rename uniqueidmanager.{cpp,h} as the class UniqueIdManager is gone

Change-Id: Iffe04bc3bb0103cbac605f0734bbfd66eb7fd854
Reviewed-on: http://codereview.qt.nokia.com/4215
Reviewed-by: Qt Sanity Bot <qt_sanity_bot@ovi.com>
Reviewed-by: hjk <qthjk@ovi.com>

src/plugins/coreplugin/coreplugin.pro

@@ -22,7 +22,7 @@ SOURCES += mainwindow.cpp \
     fancytabwidget.cpp \
     generalsettings.cpp \
     filemanager.cpp \
-    uniqueidmanager.cpp \
+    id.cpp \
     messagemanager.cpp \
     messageoutputwindow.cpp \
     outputpane.cpp \
@@ -101,7 +101,7 @@ HEADERS += mainwindow.h \
     fancytabwidget.h \
     generalsettings.h \
     filemanager.h \
-    uniqueidmanager.h \
+    id.h \
     messagemanager.h \
     messageoutputwindow.h \
     outputpane.h \