Cleanup to use imported targets.

Also updates CMake minimum version to 2.8.12.

CMakeLists.txt

-CMAKE_MINIMUM_REQUIRED(VERSION 2.8)
+CMAKE_MINIMUM_REQUIRED(VERSION 2.8.12)
 
 PROJECT(QtTesting)
 
@@ -12,16 +12,13 @@ IF(NOT (QtTesting_QT_VERSION VERSION_EQUAL "4" OR
   message(FATAL_ERROR "Expected value for QtTesting_QT_VERSION is either '4' or '5'")
 ENDIF()
 
+set(qt_imported_targets)
 IF(QtTesting_QT_VERSION VERSION_GREATER "4")
-  FIND_PACKAGE(Qt5Widgets REQUIRED)
-  ADD_DEFINITIONS(${Qt5Widgets_DEFINITIONS})
-  INCLUDE_DIRECTORIES(${Qt5Widgets_INCLUDE_DIRS})
-  SET(QT_LIBRARIES ${Qt5Widgets_LIBRARIES})
+  FIND_PACKAGE(Qt5 REQUIRED COMPONENTS Core Widgets)
+  SET(qt_imported_targets Qt5::Core Qt5::Widgets)
 ELSE()
-  IF(NOT QT4_FOUND)
-    FIND_PACKAGE(Qt4 REQUIRED)
-    INCLUDE( ${QT_USE_FILE} )
-  ENDIF()
+  FIND_PACKAGE(Qt4 REQUIRED COMPONENTS QtGui)
+  SET(qt_imported_targets Qt4::QtCore Qt4::QtGui)
 ENDIF()
 
 IF(NOT DEFINED QT_TESTING_WITH_PYTHON)
@@ -306,7 +303,7 @@ SOURCE_GROUP("Generated" FILES
 )
 
 TARGET_LINK_LIBRARIES(QtTesting
-  ${QT_LIBRARIES}
+  ${qt_imported_targets}
 )
 
 IF(QT_TESTING_WITH_PYTHON)

Testing/Cpp/CMakeLists.txt

 include(../CMake/qtTestingMacroGenerateMocs.cmake)
 
 IF(QtTesting_QT_VERSION VERSION_GREATER "4")
-  FIND_PACKAGE(Qt5Test REQUIRED)
-  ADD_DEFINITIONS(${Qt5Test_DEFINITIONS})
-  INCLUDE_DIRECTORIES(${Qt5Test_INCLUDE_DIRS})
-  SET(TEST_LIBRARIES ${Qt5Test_LIBRARIES})
+  FIND_PACKAGE(Qt5 REQUIRED QUIET COMPONENTS Test)
+  SET(TEST_LIBRARIES Qt5::Test)
 ELSE()
-  SET(TEST_LIBRARIES ${QT_QTTEST_LIBRARY})
+  FIND_PACKAGE(Qt4 REQUIRED QUIET COMPONENTS QtTest)
+  SET(TEST_LIBRARIES Qt4::QtTest)
 ENDIF()
 
 set(KIT ${PROJECT_NAME})