Fix grammar and punctuation in gui_skinning.
Note: it's "[associate **with**](https://idioms.thefreedictionary.com/associate+with)", not "associate to".
Bug: (I think) the image in the "Creating a theme" section was wrong -- the same as the one for "Customizing a control", and confusingly so.
The provided font failed to work for me, even after making copies of it with recognized font extensions.
"mytheme.thm" no longer matches any of the recognized theme extensions: *.tres, *.theme, *.res.
The example image shows it saved as a ".tres" file.
"Replace old with new." /
"Substitute new for old."
Fix punctuation in size_and_anchors.
I presume the illustrations are stragglers from an older version of Godot, the look of which I like quite a bit more.
At any rate, the current version of Godot doesn't present its options in the manner set forth by this page; there seem to have been a number of minor changes done and ``Grow Direction`` is what it pertains to now.
Ignacio Etcheverry