Take format specification history back to Cabal-1.0

[mpilgrem]

The motivation is that the documentation of the history of the format specification is almost complete (it currently stops at Cabal 1.8). This will complete it.

Some background to early Cabal version numbering is available here.

The format specification appears to have been stable between Cabal 1.2.1 and Cabal 1.6.

This PR does not modify behaviour or interface

• Patches conform to the coding conventions.
  Not applicable, but aims to be consistent with existing text.
• Is this a PR that fixes CI? If so, it will need to be backported to older cabal release branches (ask maintainers for directions).
  Not applicable.

[philderbeast]

@mpilgrem on the cabal website there are some versions of the cabal specification too. Not available at https://www.haskell.org/cabal/, but included with its repository https://github.com/haskell/cabal-website.

With haskell/cabal-website#43, that can be previewed at https://cabal.blockscope.com/pages/history.html, those cabal specifications can be viewed under the history menu.

[mpilgrem]

@philderbeast Thanks! For the purpose of the modern Cabal User Guide, I decided to treat everything before the Cabal-1.0 provided with GHC 6.4 as 'pre-history'. However, your website did help me track down:

• https://mail.haskell.org/pipermail/libraries/2003-July/001239.html (15 July 2003);
• https://www.haskell.org/cabal/old/DistUtils.tgz; and
• https://www.haskell.org/cabal/old/HIM2003Talk/LIP.pdf (29 August 2003);

which must be close to the 'source of the Nile'.

[andreasabel]

Interesting read!
(I am in no position to verify this information, but I trust you did your homework.)