unibilium: add new package

[betonmischer86]

📦 Package Details

Maintainer: @
_{(You can find this by checking the history of the package Makefile.)}

Description:
Unibilium is a very basic terminfo library. It can read and write ncurses-style terminfo files, and it can interpret terminfo format strings.

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🧪 Run Testing Details

• OpenWrt Version: OpenWrt SNAPSHOT r31813
• OpenWrt Target/Subtarget: mediatek/filogic
• OpenWrt Device: Banana Pi BPI-R4 (2x SFP+)

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✅ Formalities

• I have reviewed the CONTRIBUTING.md file for detailed contributing guidelines.

If your PR contains a patch:

• It can be applied using git am
• It has been refreshed to avoid offsets, fuzzes, etc., using

  make package/<your-package>/refresh V=s

• It is structured in a way that it is potentially upstreamable
  _{(e.g., subject line, commit description, etc.)
  We must try to upstream patches to reduce maintenance burden.}

[GeorgeSapkin]

Unless something is going to depend on this library, and nothing indicates this in either the PR or commit message, there's no point adding it.

As with the other PRs, you need to set yourself as the maintainer and don't need to include the license file.