Universal min, max, and Ordering

[runarorama]

This PR adds Universal.min and Universal.max which uses universal ordering. Also adds the Ordering type and supporting functions.

Potentially controversial decisions:

• Deleted Int.min, Int.max, Nat.min and Nat.max as these have the same implementation as Universal.min and Universal.max.
• Added patch entries for these replacements as well.
• Moved some of the tests over to under the Universal namespace but deleted redundant others.

Code review

The changes summarized below are available for you to review, using the following command:

pull-request.load https://github.com/unisonweb/base:.trunk https://github.com/runarorama/mybase:._topic.ordering

Updates:

 patch patch (added 4 updates)

Added definitions:

 unique type Ordering (+3 metadata)
 Ordering.Equal                         : Ordering
 Ordering.Greater                       : Ordering
 Ordering.Less                          : Ordering
 Ordering.andThen                       : Ordering
                                        -> Ordering
                                        -> Ordering (+3 metadata)
 Ordering.andThen.doc                   : Doc (+2 metadata)
 Ordering.andThen.example.ex1           : Ordering (+2 metadata)
 Ordering.doc                           : Doc (+2 metadata)
 Universal.compareOn                    : (a ->{e} x)
                                        -> a
                                        -> a
                                        ->{e} Ordering (+3 metadata)
 Universal.compareOn.doc                : Doc (+2 metadata)
 Universal.max                          : a -> a -> a (+3 metadata)
 Universal.max.doc                      : Doc (+2 metadata)
 Universal.max.tests.absorption         : [Test.Result] (+2 metadata)
 Universal.max.tests.associative        : [Test.Result] (+4 metadata)
 Universal.max.tests.commutative        : [Test.Result] (+4 metadata)
 Universal.max.tests.distributesOverMin : [Test.Result] (+2 metadata)
 Universal.max.tests.idempotent         : [Test.Result] (+2 metadata)
 Universal.max.tests.partialOrder       : [Test.Result] (+4 metadata)
 Universal.min                          : a -> a -> a (+3 metadata)
 Universal.min.doc                      : Doc (+2 metadata)
 Universal.min.tests.absorption         : [Test.Result] (+4 metadata)
 Universal.min.tests.associative        : [Test.Result] (+3 metadata)
 Universal.min.tests.commutative        : [Test.Result] (+3 metadata)
 Universal.min.tests.distributesOverMax : [Test.Result] (+2 metadata)
 Universal.min.tests.idempotent         : [Test.Result] (+2 metadata)
 Universal.min.tests.partialOrder       : [Test.Result] (+2 metadata)
 Universal.ordering                     : a -> a -> Ordering (+3 metadata)
 Universal.ordering.doc                 : Doc (+2 metadata)
 Universal.ordering.doc.snippet1        : Doc (+2 metadata)

Removed definitions:

 Int.max                           : Int -> Int -> Int
 Int.max.doc                       : Doc
 ┌ Int.max.tests.absorption        : [Test.Result]
 └ Int.min.tests.absorption
 Int.max.tests.associative         : [Test.Result]
 Int.max.tests.commutative         : [Test.Result]
 Int.max.tests.deMorgan            : [Test.Result]
 Int.max.tests.distributesOverMin  : [Test.Result]
 Int.max.tests.idempotent          : [Test.Result]
 Int.max.tests.partialOrder        : [Test.Result]
 Int.max.tests.top                 : [Test.Result]
 Int.min                           : Int -> Int -> Int
 Int.min.doc                       : Doc
 Int.min.tests.associative         : [Test.Result]
 Int.min.tests.bottom              : [Test.Result]
 Int.min.tests.commutative         : [Test.Result]
 Int.min.tests.deMorgan            : [Test.Result]
 Int.min.tests.distributesOverMax  : [Test.Result]
 Int.min.tests.idempotent          : [Test.Result]
 Int.min.tests.partialOrder        : [Test.Result]
 Nat.max                           : Nat -> Nat -> Nat
 Nat.max.doc                       : Doc
 Nat.max.tests.absorption          : [Test.Result]
 Nat.max.tests.additionDistributes : [Test.Result]
 Nat.max.tests.associative         : [Test.Result]
 Nat.max.tests.commutative         : [Test.Result]
 Nat.max.tests.distributesOverMin  : [Test.Result]
 Nat.max.tests.idempotent          : [Test.Result]
 Nat.max.tests.identity            : [Test.Result]
 Nat.max.tests.partialOrder        : [Test.Result]
 ┌ Nat.max.tests.summation         : [Test.Result]
 └ Nat.min.tests.summation
 Nat.min                           : Nat -> Nat -> Nat
 Nat.min.doc                       : Doc
 Nat.min.tests.additionDistributes : [Test.Result]
 Nat.min.tests.associative         : [Test.Result]
 Nat.min.tests.commutative         : [Test.Result]
 Nat.min.tests.distributesOverMax  : [Test.Result]
 Nat.min.tests.idempotent          : [Test.Result]
 Nat.min.tests.identity            : [Test.Result]
 Nat.min.tests.partialOrder        : [Test.Result]

[pchiusano]

LGTM, merged in #7mrc1t233q