dd316e4d14 pow: Remove Mul/Div by arbitrary integer types (Tobin C. Harding)
Pull request description:
When we added `Target` and `Work` types we implemented multiplication and division by anything `Into<u64>`, this is not typically done in the Rust stdlib and also is semantically incorrect for the types.
Remove `Mul` and `Div` impls from `Target` and `Work`. Also remove `Mul<T>` for `T: Into<u64>` from the private `U256` type.
Fix#1632
ACKs for top commit:
apoelstra:
ACK dd316e4d14
Kixunil:
ACK dd316e4d14
Tree-SHA512: ede53555844adab321ff344535b7b8bab3c5c73855823dfc3ad728b077ae199451b7e22a1d203ef73a076073b7f0cbf9637cefa5fe82fc78ab454d02fa0b62b9