readAFolder and folder browser bug fix

While working on the API documentation I found a bug with reading contents of folders and ended up improving some stuff while fixing it. 📂🪲

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Fixes:

Now when you use a folder browse element or the helper function we accurately return the file size for files in the contents object.

//Read the contents of a specific folder and store them in a variable
var catPics = ugui.helpers.readAFolder("C:/pictures/cats");
//Returns an object of each item in the root of the folder with size and isFolder properties
catPics.contents;

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Breaking Changes:

Previously to get the array of item names from a folder you'd need to do:

//Returns an array of the names of all items in the root of the folder
catPics.contents._folder_contents_array;

Which was confusing and bad, so if you were using that you'll need to change it to

//Returns an array of the names of all items in the root of the folder
catPics.contentsList;

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I'm not bumping this from 1.1.2 to 2.0.0 because this is a very minor breaking change that likely no one was using anyway.