Paused contract: burn() behaviour before/after 0.6.0

Support Contracts
4

Hi @jmahhh,

This would be a breaking change going from OpenZeppelin Contracts 2.5 to 3.0.
OpenZeppelin Contracts 2.5 Pausable didn’t pause ERC20 burn.
OpenZeppelin Contracts 3.0 Pausable does pause ERC20 burn.

See OpenZeppelin Contracts API Stability for details on when breaking changes may occur.

Would be great to get your feedback on this change.