Rubber-stamped (reluctantly) by Kevin McCullough.

        Rename date_object.h/cpp to DateInstance.h/cpp

        * GNUmakefile.am:
        * JavaScriptCore.pri:
        * JavaScriptCore.vcproj/JavaScriptCore/JavaScriptCore.vcproj:
        * JavaScriptCore.xcodeproj/project.pbxproj:
        * JavaScriptCoreSources.bkl:
        * kjs/AllInOneFile.cpp:
        * kjs/DateConstructor.cpp:
        * kjs/DateInstance.cpp: Copied from kjs/date_object.cpp.
        * kjs/DateInstance.h: Copied from kjs/date_object.h.
        * kjs/DatePrototype.cpp:
        * kjs/DatePrototype.h:
        * kjs/date_object.cpp: Removed.
        * kjs/date_object.h: Removed.



git-svn-id: http://svn.webkit.org/repository/webkit/trunk@34897 268f45cc-cd09-0410-ab3c-d52691b4dbfc