Remove console.logs

Using console in production is generally undesirable due to
performance loss and security concerns. Errors were changed
to console.error and console.logs were removed.

dev-scripts/dev.js

@@ -37,7 +37,7 @@ function startServer () {
           resolve()
         } else {
           if (!firstRun) {
-            console.log(stats.compilation.errors[0])
+            return
           } else {
             firstRun = false
             reject(stats.compilation.errors[0])