Examples, units and domains in math function comments

[Onetchou]

Solves #1149

[what-the-diff]

PR Summary

Yay! Significant adjustments have been made to uplift the experience of everyone using our app. You're absolutely going to love it! 😍

• Enhanced Function Descriptions in vtranslatevars.cpp
  In our quest to become more user-friendly, the descriptions of our various mathematical functions have been spruced up. 🚀 Now, they come bundled with nuggets of examples showcasing their usage and the expected output. This is akin to getting a mini-tutor within the app! Learning made fun! 🎓

• Tweaked Dialog Display in edit_formula_dialog.ui
  Our dialog displays in the app got a fresh coat of paint when it comes to their layouts! 😎

  • The dialog's height?—Pushed the ruler a bit and sprung it up from 510 to 520 pixels! 📏 Extra room always means extra comfort.
  • And guess what? Each QListWidget's item enjoyed a similar growth spurt! From a compact 40, they sprang up to a glorious 50 pixels. 🎉 More space for better interactions!

Every step here makes your experience more seamless. Let's enjoy this journey of continuous improvement together! 🌈🚀💗

[DSCaskey]

Looks good to me.