Merge branch 'master' into develop

Author: krzysg

CMakeLists.txt

@@ -84,8 +84,14 @@ endif(APR_BUILD_EXAMPLES)
 option (APR_TESTS "Build tests wrappers" OFF)
 if(APR_TESTS)
     message(STATUS "APR: Building tests")
-    add_subdirectory("external/gtest")
-    set(GTEST_LIBRARIES gtest)
+    find_package(GTest 1.8.0)
+    if(GTEST_FOUND)
+        include_directories(${GTEST_INCLUDE_DIRS})
+    else(GTEST_FOUND)
+        message(STATUS "APR: GTest not found, using internal gtest")
+        add_subdirectory("external/gtest")
+        set(GTEST_LIBRARIES gtest)
+    endif(GTEST_FOUND)
     add_subdirectory(test)
 endif(APR_TESTS)