Merge topic 'use-generator-target'

d8f8940b cmGeneratorTarget: Move IsCFBundleOnApple from cmTarget.
7550879f cmGeneratorTarget: Move IsXCTestOnApple from cmTarget.
88d10d55 cmGeneratorTarget: Copy IsAppBundleOnApple from cmTarget.
b5f5de70 cmGeneratorTarget: Copy IsFrameworkOnApple from cmTarget.
8e20ea6e cmGeneratorTarget: Move IsLinkable from cmTarget.
a527abf0 Xcode: Port internal API to cmGeneratorTarget.
eb3be7d6 cmGeneratorTarget: Move GetExportName from cmTarget.
d231c31b Export: Port internal API to cmGeneratorTarget.
e6661282 Export: Port internal utility to cmGeneratorTarget.
2b9cc1e2 Export: Port some API to cmGlobalGenerator.
97062ac2 cmInstallTargetGenerator: Port GetInstallFilename to cmGeneratorTarget.
6a72b3c8 Export: Port interface to cmGeneratorTarget.
1293c156 cmExportTryCompileFileGenerator: Port to cmGeneratorTarget.
381e7afd cmExportSet: Store a cmGeneratorTarget.
65911cae cmGlobalGenerator: Compute export() related classes early.
37ab74a6 cmLocalGenerator: Port PList handling to cmGeneratorTarget.
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