fixing travis

scripts/release.js

 function calcNewVersion() {
   const packageVersion = semver.clean(process.env.npm_package_version);
   console.log(`package version: ${packageVersion}`);
-  exec.execSync(`git fetch`);
+  exec.execSync(`git fetch --unshallow`);
   const commitCount = exec.execSyncRead(`git rev-list --count ${ONLY_ON_BRANCH}`);
   console.log(`commits in ${ONLY_ON_BRANCH}: ${commitCount}`);
   return `${semver.major(packageVersion)}.${semver.minor(packageVersion)}.${commitCount}`;