Improve Bounties and Child Bounties Deposit Logic (#11014)

* basic idea

* make tests better

* update bounties pallet to also have similar logic

* new test verifies logic for bounty pallet

* add test for new child logic

* better name

* make `node` compile with bounties changes

* * formatting
* use uniform notion of parent and child, no "master" or "general" entity
* README updated to match comments

* Revert "* formatting"

This reverts commit 1ab729e7c23b5db24a8e229d487bbc2ed81d38c3.

* update bounties logic to use bounds

* fix child

* bounties test for max

* update tests

* check min bound

* update node

* remove stale comment

* Update frame/bounties/src/lib.rs

Co-authored-by: Dan Shields <[email protected]>