Added CMake variable to enable unit tests.

CMakeLists.txt

@@ -1,13 +1,27 @@
 cmake_minimum_required (VERSION 2.6)
 project (libsettable)
 
-find_package(Boost 1.42 COMPONENTS system unit_test_framework)
+
+if (NOT ${tests})
+	set(enable_tests "off")
+else()
+	set(enable_tests "on")
+endif()
+
+if (${enable_tests} STREQUAL "on")
+	find_package(Boost 1.42 COMPONENTS system unit_test_framework)
+else()
+	find_package(Boost)
+endif()
 
 include_directories(${PROJECT_SOURCE_DIR}/src
                     ${Boost_INCLUDE_DIRS})
 
 add_subdirectory(examples)
 
-enable_testing()
 
-add_subdirectory(unittest)
+
+if (${enable_tests} STREQUAL "on")
+	enable_testing()
+	add_subdirectory(unittest)
+endif()