run tests also on 32 bit binaries

.travis.yml

@@ -45,7 +45,11 @@ script:
    - make
    - echo "Generate documentation"
    - make doc
-   - echo "Debug build and unit tests"
+   - echo "Debug build and unit tests (32 bit)"
+   - make clean
+   - cmake -DCMAKE_C_FLAGS=-m32 -DCMAKE_BUILD_TYPE=Debug -DENABLE_UNIT_TESTS=ON -DENABLE_COVERAGE=ON ..
+   - make && make test
+   - echo "Debug build and unit tests (64 bit)"
    - make clean
    - cmake -DCMAKE_BUILD_TYPE=Debug -DENABLE_UNIT_TESTS=ON -DENABLE_COVERAGE=ON .. 
    - make && make test