Flexbox docs

Updated the flexbox documentation for the current flexbox implementation

docs/objects/Flexbox/getJustifyContent.md

@@ -0,0 +1,20 @@
+## getJustifyContent
+
+### Description
+
+Returns the current method used for aligning the child objects along the main axis within the Flexbox.
+
+### Returns
+
+1. `string` The method used for aligning the child objects. Possible values are: `flex-start`, `flex-end`, `center`, `space-between`, `space-around`, and `space-evenly`.
+
+### Usage
+
+* Creates a default Flexbox, sets the justify content, and then retrieves it.
+
+```lua
+local main = basalt.createFrame()
+local flexbox = mainFrame:addFlexbox()
+      :setJustifyContent("space-between")
+local justifyContent = flexbox:getJustifyContent() -- returns "space-between"
+```