Removing core-spec.pdf from repository?

[Phil Ruffwind]

On Tue, Mar 14, 2017, at 10:20, Elliot Cameron wrote:
> The only loss is the ability to look at changes over time.

GHC docs are archived for every version number:

https://downloads.haskell.org/~ghc/<version>/...

So it would remain possible to compare the changes between each release.
 The only problem is the discontinuity caused by this migration.