cmLocalGenerator: Port some API to cmGeneratorTarget.

Source/cmCommonTargetGenerator.cxx

Source/cmExtraSublimeTextGenerator.cxx

Source/cmGhsMultiTargetGenerator.cxx

Source/cmGlobalXCodeGenerator.cxx

Source/cmLocalGenerator.cxx

Source/cmLocalGenerator.h

Source/cmLocalUnixMakefileGenerator3.cxx

Source/cmLocalUnixMakefileGenerator3.h

Source/cmLocalVisualStudio6Generator.cxx

Source/cmLocalVisualStudio7Generator.cxx

Source/cmMakefileExecutableTargetGenerator.cxx

Source/cmMakefileLibraryTargetGenerator.cxx

Source/cmMakefileTargetGenerator.cxx

Source/cmMakefileUtilityTargetGenerator.cxx

Source/cmNinjaNormalTargetGenerator.cxx

Source/cmNinjaTargetGenerator.cxx

Source/cmQtAutoGeneratorInitializer.cxx

Source/cmVisualStudio10TargetGenerator.cxx