chore: unite all token_bucket implementation into single place under nim-chronos

[NagyZoltanPeter]

Background

When implementing DOS protection for nwaku we found the chronos implements token_bucket but has limitations and an issue that prevented use for nwaku purposes.
Now chat-sdk needs similar functionality with some extension (#3497).
It means we are spreading slightly different implementation of the same solution.

Details

We aim to make all these implementation sourced back to origin into chronos library.

• The final solution shall cover the fixed version of original feature set
• Shall cover the nwaku needs for currently implemented DOS protection rate limiter.
• To be extended with chat-sdk interface

Acceptance criteria

chronos, libp2p (original user of chronos' token_bucket), nwaku tests shall pass with original requirements.
chat-sdk shall be capable to use it directly from chronos without further needs.

[NagyZoltanPeter]

First phase is done:
Made a single TokenBucket implementation in nim-chronos that satisfies nim-waku and nim-chat-sdk needs withouth compromising original nim-chronos implementations' backward compatibility.

status-im/nim-chronos#582
Once accepted and merged, I can continue to get it into use in nim-waku and drop the local implementation.

cc: @plopezlpz