Add concise Julia version formatter

[fingolfin]

Co-authored-by: Codex codex@openai.com

Resolves #109.

Before:

$ juliaup  list
 Channel                Version
---------------------------------------------------------------
 0                      0.7.0+0.x64.apple.darwin14
 0.7                    0.7.0+0.x64.apple.darwin14
 0.7.0                  0.7.0+0.x64.apple.darwin14
 0.7.0~x64              0.7.0+0.x64.apple.darwin14
 0.7~x64                0.7.0+0.x64.apple.darwin14
 0~x64                  0.7.0+0.x64.apple.darwin14
 1                      1.12.6+0.aarch64.apple.darwin14
 1.0                    1.0.5+0.x64.apple.darwin14
 1.0.0                  1.0.0+0.x64.apple.darwin14
 1.0.0~x64              1.0.0+0.x64.apple.darwin14
 1.0.1                  1.0.1+0.x64.apple.darwin14
 1.0.1~x64              1.0.1+0.x64.apple.darwin14
...
 release                1.12.6+0.aarch64.apple.darwin14
 release~aarch64        1.12.6+0.aarch64.apple.darwin14
 release~x64            1.12.6+0.x64.apple.darwin14
 nightly                latest-macos-aarch64
 nightly~aarch64        latest-macos-aarch64
 nightly~x64            latest-macos-x86_64
 x.y-nightly            x.y-nightly-macos-aarch64
 x.y-nightly~aarch64    x.y-nightly-macos-aarch64
 x.y-nightly~x64        x.y-nightly-macos-x86_64
 pr{number}             pr{number}-macos-aarch64
 pr{number}~aarch64     pr{number}-macos-aarch64
 pr{number}~x64         pr{number}-macos-x86_64

After:

$ ./target/debug/juliaup list
 Channel                Version
--------------------------------------------------
 0                      0.7.0
 0.7                    0.7.0
 0.7.0                  0.7.0
 0.7.0~x64              0.7.0
 0.7~x64                0.7.0
 0~x64                  0.7.0
 1                      1.12.6
 1.0                    1.0.5
 1.0.0                  1.0.0
 1.0.0~x64              1.0.0
 1.0.1                  1.0.1
 1.0.1~x64              1.0.1
...
 release                1.12.6
 release~aarch64        1.12.6
 release~x64            1.12.6
 nightly                latest-macos-aarch64
 nightly~aarch64        latest-macos-aarch64
 nightly~x64            latest-macos-x86_64
 x.y-nightly            x.y-nightly-macos-aarch64
 x.y-nightly~aarch64    x.y-nightly-macos-aarch64
 x.y-nightly~x64        x.y-nightly-macos-x86_64
 pr{number}             pr{number}-macos-aarch64
 pr{number}~aarch64     pr{number}-macos-aarch64
 pr{number}~x64         pr{number}-macos-x86_64

[IanButterworth]

I don't really understand why this is better?

At least it should be something like this, no?

 release                1.12.6
 release~aarch64        1.12.6+0.aarch64.apple.darwin14
 release~x64            1.12.6+0.x64.apple.darwin14

But I think the current thing is fine?

[fingolfin]

I've just resolved conflicts; @davidanthoff @IanButterworth is this in the direction you'd want #109 resolved? It seems nicer to me, but perhaps you have other preferences.