Make tests conditional

--- CMakeLists.txt.orig	2018-04-11 16:05:28 UTC
+++ CMakeLists.txt
@@ -15,7 +15,7 @@ include(FeatureSummary)
 # check for PkgConfig, Qt and MPIR/GMP
 find_package(PkgConfig)
 if(BUILD_QT4)
-    find_package(Qt4 REQUIRED COMPONENTS QtCore QtDBus QtTest)
+    find_package(Qt4 REQUIRED COMPONENTS QtCore QtDBus)
     set(QT_USE_LIBSPREFIX Qt4::Qt)
     set(ALKIMIA_LIB_SUFFIX "")
     set(ALKIMIA_INCLUDE_SUFFIX "Qt4")
@@ -23,7 +23,7 @@ if(BUILD_QT4)
     set(PC_TARGET_QTPREFIX Qt)
     set(PC_TARGET_SUFFIX)
 else()
-    find_package(Qt5 REQUIRED COMPONENTS Core DBus Test)
+    find_package(Qt5 REQUIRED COMPONENTS Core DBus)
     set(QT_USE_LIBSPREFIX Qt5::)
     set(ALKIMIA_LIB_SUFFIX "5")
     set(ALKIMIA_INCLUDE_SUFFIX "Qt5")
@@ -59,4 +59,7 @@ add_definitions(-DQT_USE_FAST_CONCATENATION -DQT_USE_F
 include_directories(${MP_INCLUDE_DIR})
 
 add_subdirectory(src)
-add_subdirectory(autotests)
+
+if(BUILD_TESTING)
+    add_subdirectory(autotests)
+endif()