Remove JSX since we don't use it.

scripts/pre-commit

 #!/bin/sh
-jsfiles=$(git diff --cached --name-only --diff-filter=ACM "*.js" "*.jsx" | tr '\n' ' ')
+jsfiles=$(git diff --cached --name-only --diff-filter=ACM "*.js" | tr '\n' ' ')
 [ -z "$jsfiles" ] && exit 0
 # Prettify all staged .js files