ENH: Add cmTarget::GetLinkInformation method to allow several places in the generators to share link information while only computing it once per configuration for a target.  Use it to simplify the chrpath feature.

ENH:  Allow QT4_WRAP_CPP to work with dir1/myobject.h dir2/myobject.h
      Fixes #5067.

  - Added EXACT option to request an exact version.
  - Enforce version using check provided by package.
  - Updated FindPackageTest to test versioning in config mode.

ENH:  Improve find for glib/gthread when Qt is configured to use it.
      Fixes #6220.

ENH: Document PRIVATE_HEADER, PUBLIC_HEADER, and RESOURCE target properties and corresponding arguments to INSTALL(TARGETS).

BUG: Fix Framework test after fixing FRAMEWORK targets to not install like frameworks on non-Apple systems.

  - Imported bundles have the MACOSX_BUNDLE property set
  - Added cmTarget::IsAppBundleOnApple method to simplify checks
  - Document BUNDLE keyword in INSTALL command
  - Updated IMPORTED_LOCATION property documentation for bundles
  - Updated ExportImport test to test bundles

  - Imported frameworks have the FRAMEWORK property set
  - Added cmTarget::IsFrameworkOnApple method to simplify checks
  - Also remove separate IMPORTED_ENABLE_EXPORTS property and just use ENABLE_EXPORTS since, like FRAMEWORK, it just represents the target type.
  - Document FRAMEWORK keyword in INSTALL command.
  - Updated IMPORTED_LOCATION property documentation for Frameworks

COMP: Add virtual destructor to cmExportFileGenerator to avoid warnings about other virtual functions.

  - Created cmExportFileGenerator hierarchy to implement export file generation
  - Installed exports use per-config import files loaded by a central one.
  - Include soname of shared libraries in import information
  - Renamed PREFIX to NAMESPACE in INSTALL(EXPORT) and EXPORT() commands
  - Move addition of CMAKE_INSTALL_PREFIX to destinations to install generators
  - Import files compute the installation prefix relative to their location when loaded
  - Add mapping of importer configurations to importee configurations
  - Rename IMPORT targets to IMPORTED targets to distinguish from windows import libraries
  - Scope IMPORTED targets within directories to isolate them
  - Place all properties created by import files in the IMPORTED namespace
  - Document INSTALL(EXPORT) and EXPORT() commands.
  - Document IMPORTED signature of add_executable and add_library
  - Enable finding of imported targets in cmComputeLinkDepends

  - This will be useful for imported library dependencies
  - Replaces old cmTarget analyze-lib-depends stuff for linking
  - Formalizes graph construction and dump
  - Explicitly represents dependency inferral sets
  - Use BFS of initial dependencies to preserve order

ENH: Apply new implicit link directory find_library policy when loading a cache from an earlier CMake.

ENH: Added cmMakefile::NeedCacheCompatibility method and support for it in cmCacheManager.  This will allow commands to modify their behavior when running with a cache loaded from an earlier CMake version.

Alex