Add support for negative values

[gsmecher]

This is an updated version of #153, and should clear up https://github.com/tenox7/ttyplot/issues/53 and https://github.com/tenox7/ttyplot/issues/22.

This is a quick and possibly rough implementation - comments welcome. The rebase looks clean enough, but I admit to rushing through it.

[hartwork]

@gsmecher just a quick note that with the next push your CI here will be red due to meantime changes at https://apt.llvm.org/ unless you rebase onto latest master where pull request #170 with a fix has been merged. Thanks!

[gsmecher]

@gsmecher just a quick note that with the next push your CI here will be red due to meantime changes at https://apt.llvm.org/ unless you rebase onto latest master where pull request #170 with a fix has been merged. Thanks!

Thanks - I have rebased and force-pushed, removing the bogus array size check at the same time.

[edgar-bonet]

@gsmecher: There is something wrong with your last force-push. The previous one (77fb446) was, as expected, based on master. The last one (3d83c57) is based on master~ and carries copies of the two commits of #170, with different Committer name:

* 3d83c57 (pull/169/head) Add support for negative values.
* 622f3a9 stresstest: add -n flag to remove positive bias (emit negative values)
* 6d24924 Don't use FLT_MIN - 0 is the correct value here.
* 1c579ef linux_and_macos.yml: Drop compilation with Clang 17
* bb6a97d linux_and_macos.yml: Get installation of Clang 18 on Linux back in sy>
* 5b64245 Move global variables that are only locally used into local scope.
| * 77fb446 Add support for negative values.
| * 0f1ae18 stresstest: add -n flag to remove positive bias (emit negative valu>
| * 216be4a Don't use FLT_MIN - 0 is the correct value here.
| * 0eb1356 Move global variables that are only locally used into local scope.
| * f98f2f2 (master) Merge pull request #170 from hartwork/fix-linux-ci
|/| 
| * 321ebd5 linux_and_macos.yml: Drop compilation with Clang 17
| * aef9d29 linux_and_macos.yml: Get installation of Clang 18 on Linux back in >
|/  
* 374bca3 readme update

Also, I had to unresolve a couple of review comments.

[gsmecher]

My apologies. I am trying to keep this as a "side distraction" - which isn't fair if it pushes work onto you.

I have rebased onto f98f, and can see the correct commit history since then. I'll force-push that now, then look into the resolved/unresolved comments. Thanks for bearing with me.

[tenox7]

Do you want me to merge?

[edgar-bonet]

Do you want me to merge?

Yes please. I would rather let you have the final call.

[tenox7]

Thank you!