[Structure] Add GUI or form elements

[geekygirlsarah]

Description

This issue is for adding a new structure for all languages that will let you compare a new aspect of a language. Ideally someone with many programming languages will help work on this.

This structure should show how you can create windows, text boxes, or other GUI-type elements. This could be:

• How to create basic windows as well as various properties like if they're resizable (if it's built into the language)
• How to add typical form components (labels, text boxes, check boxes, buttons, etc.). This could be web based or desktop application programs.
• How to add non-form components (images, frames, etc.)
• How to change layouts of a window (like Java's swingx components)
• Are there differences in things between Windows, Mac, Linux, or other OSes?

Or other things. It should take some thought on all of the features that any programming language could have. Upon making this PR, expect it to have some revisions as people from various programming language backgrounds offer suggestions.

Requirements

1. Look over the documentation at https://docs.codethesaur.us/thesaurus/add-new-structure/
2. Add a new file under web/thesauruses/_meta named whatever feels appropriate
3. Open up web/thesauruses/meta_info.json and add your new file to that file in the structures section.
4. Add in some categories, then add in the concepts under that
5. Feel free to use any _meta file as examples for how to do it
6. Make a PR and we can help test and review it