Allow LOCATION property at configure time only on IMPORTED targets.
Don't allow include() of the result of export().
Add more cmGeneratorTarget API to cmGlobalGenerator.
Move GetLocation to cmGeneratorTarget.
Move GetFullPath to cmGeneratorTarget
Port cmExportBuildFileGenerator to cmGeneratorTarget.
Port some of the cmExportFileGenerator API to cmGeneratorTarget.

Enough to make it more possible to move GetLinkInterface
to cmGeneratorTarget.
Move GetIncludeDirectories to cmGeneratorTarget.

Accessor methods for other properties can similarly be moved.
Move GetSOName to cmGeneratorTarget.
Move GetAutoUicOptions to cmGeneratorTarget.
Move GetLinkInformation to cmGeneratorTarget

This is a updated version of 4f5384e75c6a00d110d3fa3f555a3f6a4f31bb46
which was reverted in commit 0bbae6f95f55f23b758780f771bf4dd560ac2c07.
Move GetExecutableNames to cmGeneratorTarget.
Move GetLibraryNames to cmGeneratorTarget.
Move HasSOName to cmGeneratorTarget.
Move GetPDBName to cmGeneratorTarget.
Move NeedRelinkBeforeInstall to cmGeneratorTarget.
Move IsChrPathUsed to cmGeneratorTarget.
Move GetFullNameComponents to cmGeneratorTarget.
Move GetMacContentDirectory to cmGeneratorTarget.
Move GetInstallNameDir* to cmGeneratorTarget.