Make "getTermSize()" use local variables instead of package-level ones

[VoIdemar]

[Adaendra]

Hi @VoIdemar To let you know, I've made a fork of this project as it hasn't been updated for years. Here is the link : https://github.com/Adaendra/uilive/tree/master In the latest version by my side, I've included your MR.