Add Catch2 and Google Test on Cmake

ToDo:
- Add compiling QElectroTech on Cmake (help needed)
- more Tests?
   - Qt Test
   - Boost Test

to test
run qtcreator
File >  open => CMakeLists.txt

tests/CMakeLists.txt

@@ -0,0 +1,28 @@
+# Copyright 2006 The QElectroTech Team
+# This file is part of QElectroTech.
+#
+# QElectroTech is free software: you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation, either version 2 of the License, or
+# (at your option) any later version.
+#
+# QElectroTech is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with QElectroTech. If not, see <http://www.gnu.org/licenses/>.
+
+cmake_minimum_required(VERSION 3.5)
+
+message("_____________________________________________________________________")
+project(unittests LANGUAGES CXX)
+
+message("PROJECT_NAME:       " ${PROJECT_NAME})
+message("PROJECT_SOURCE_DIR: " ${PROJECT_SOURCE_DIR})
+message("QET_DIR:            " ${QET_DIR})
+
+# Add sub directories
+add_subdirectory(catch)
+add_subdirectory(googletest)