Remove woo table templates and alert clean-up

[crftwrk]

As described in #333, Woo templates should be reduced for less maintenance and more stability.

This PR does it with most rounded class in templates.

• Removed the last alert alert-* and replaces them by woocommerce-* classes. Due to Make icons in alerts optional and use masks instead of FA font #403, all Woo alerts have now an icon, default alerts not.
• Removed most rounded classes in templates and replaces tem by border-radius: $border-radius;.
• 6 files that only had changes in the rounded class has been deleted
• Minor improvements in the _scss files

This has no impact on the frontend. Tested, works fine and is already live on bootscore.me. Just click through the store and check button classes in cart, checkout and dashboard.

@justinkruit if you agree, I'm happy when you just hit the merge button.

[justinkruit]

I'm always up for removing WooCommerce template parts as they're a pain in the butt to maintain. All looks good 👍