DIP 1029---Add throw as Function Attribute---Community Review Round 1

[Walter Bright]

On 1/14/2020 7:18 AM, Arine wrote:
> Otherwise this shouldn't be it's own DIP. If the intention is this is only 
> required for another DIP, this should just be included in that DIP.
It does make sense on its own.

Furthermore, I don't want to distract the coming discussion on "nothrow as 
default" with all the debate about throw vs throws vs @throw, etc.

BTW, anyone wanting to discuss the merits of "nothrow as default" please use the 
"nothrow by default" thread started by Steven Schveighoffer on Jan 4.