Remove babel-cli dependency

At this point, we might as well use babel-core directly.

New system supports source maps for `battledata` and `graphics`! Woo!

It also logs the compile step.

Author: Zarel

.github/workflows/test.yml

@@ -16,7 +16,7 @@ jobs:
 
     strategy:
       matrix:
-        node-version: [12.x]
+        node-version: [14.x]
 
     steps:
     - uses: actions/checkout@v2