Update .travis.yml

Author: Beakerboy

.travis.yml

@@ -13,7 +13,7 @@ after_success:
   - mkdir $TRAVIS_BUILD_DIR/.ND_Config
   - cp .nd_project.txt $TRAVIS_BUILD_DIR/.ND_Config/Project.txt
   - mono /tmp/Natural\ Docs/NaturalDocs.exe $TRAVIS_BUILD_DIR/.ND_Config
-  - python3 Excel-Addin-Generator/excelAddinGenerator/main.py $TRAVIS_BUILD_DIR/bin/vbaProject.bin SQLlib.xlam
+  - python3.5 Excel-Addin-Generator/excelAddinGenerator/main.py $TRAVIS_BUILD_DIR/bin/vbaProject.bin SQLlib.xlam
 deploy:
   - provider: pages
     skip_cleanup: true