fix travis build issue with latest npm

.travis.yml

@@ -27,6 +27,7 @@ cache:
 before_install:
   - if [[ "$TRAVIS_OS_NAME" == "linux" ]]; then export CC=gcc-7 && CXX=g++-7; fi
   - if ! [[ "$TRAVIS_OS_NAME" == "windows" ]]; then npm run fetch-libsodium; fi
+  - if [[ "$TRAVIS_OS_NAME" == "windows" ]]; then node `npm prefix -g`/node_modules/npm/bin/npm-cli.js i -g [email protected]; fi # node-gyp 5.0.5 does not work so downgrade npm until they release with node-gyp@6
 
 before_deploy:
   - ARCHIVE_NAME="${TRAVIS_TAG:-latest}-$TRAVIS_OS_NAME-`uname -m`.tar"

CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## Current
 
+## v2.4.9
+
+* Downgrades npm on travis to 6.11.x as we cannot build prebuilds with [email protected]. Can be upgraded again when npm ships node-gyp@6.
+
 ## v2.4.8
 
 * Removing Node 4 and 6 from Travis as the config does not work there. We still build for 4 and 6 though.