Upgrading to this version (best way)
1. Backup your old version files.
2. Run 2.4 on a local or test server to test its new features.
3. Make everything as you wish for.
4. Make it public on your server.

Upgrading (my way)
1. Add the following line to Messages.yml:
Tool-Required-Error: "&cYou can only break this block with a &b%tool%&c."
2. Add tool-required to Blocklist.yml if you wish to do this.

Default Blocklist.yml: https://github.com/Aurorion/BlockRegen/blob/master/Blocklist.yml
Default Messages.yml: https://github.com/Aurorion/BlockRegen/blob/master/Messages.yml

Added
- Added a new option called " tool-required".
This option allows you to set a tool that people need to have to break the block.
- Intergrated Bstats.org (usefull for me, you can always opt-out but as this is a free resource I would like you to not do that)
- Added the full source-code to Github. I'm kinda new to Github as I never needed to add something to it. Sorry if I mess up.

Source-Code: https://github.com/Aurorion/BlockRegen

Have a nice day!
~ Aurorion