Factor out bitwise operator in indexOf test

Author: Patrick Dillon

packages/create-react-app/index.js

@@ -152,7 +152,7 @@ function getInstallPackage(version) {
 
 // Extract package name from tarball url or path.
 function getPackageName(installPackage) {
-  if (~installPackage.indexOf('.tgz')) {
+  if (installPackage.indexOf('.tgz') > 0) {
     return installPackage.match(/^.+\/(.+)-.+\.tgz$/)[1];
   } else if (installPackage.indexOf('@') > 0) {
     return installPackage.charAt(0) + installPackage.substr(1).split('@')[0];