only release on tags

ladyada · ladyada · commit 9f6dcd490cf8 · 2018-09-26T11:20:49.000-04:00
diff --git a/.travis.yml b/.travis.yml
@@ -12,6 +12,8 @@ deploy:
   file: "$TRAVIS_BUILD_DIR/bundles/*"
   skip_cleanup: true
   overwrite: true
+  on:
+    tags: true
 - provider: pypi
   user: adafruit-travis
   on:
