Improve markdown and fix links that don't render correctly

doc/development/ux_guide/tips.md

 # Tips
-## Contents
-* [SVGs](#svgs)
-
----
-
 ## SVGs
 When exporting SVGs, be sure to follow the following guidelines:
 1. Convert all strokes to outlines.
-2. Use pathfinder tools to combine overlapping paths and create compound paths.
-3. SVGs that are limited to one color should be exported without a fill color so the color can be set using CSS.
-4. Ensure that exported SVGs have been run through an [SVG cleaner](https://github.com/RazrFalcon/SVGCleaner) to remove unused elements and attributes.
-You can open your svg in a text editor to ensure that it is clean.
+1. Use pathfinder tools to combine overlapping paths and create compound paths.
+1. SVGs that are limited to one color should be exported without a fill color so the color can be set using CSS.
+1. Ensure that exported SVGs have been run through an [SVG cleaner](https://github.com/RazrFalcon/SVGCleaner) to remove unused elements and attributes.
+
+You can open your SVG in a text editor to ensure that it is clean.
 Incorrect files will look like this:
 ```xml
@@ -35,10 +31,10 @@ Incorrect files will look like this:
 </svg>
 ```
-Correct file will look like this:
+Correct files will look like this:
 ```xml
 <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 16 17" enable-background="new 0 0 16 17"><path d="m15.1 1h-2.1v-1h-2v1h-6v-1h-2v1h-2.1c-.5 0-.9.5-.9 1v14c0 .6.4 1 .9 1h14.2c.5 0 .9-.4.9-1v-14c0-.5-.4-1-.9-1m-1.1 14h-12v-9h12v9m0-11h-12v-1h12v1"/><path d="m5.4 11.6l1.5 1.2c.4.3 1.1.3 1.4-.1l2.5-3c.3-.4.3-1.1-.1-1.4-.5-.4-1.1-.3-1.5.1l-1.8 2.2-.8-.6c-.4-.3-1.1-.3-1.4.2-.3.4-.3 1 .2 1.4"/></svg>
 ```
-> TODO: Checkout [https://github.com/svg/svgo](https://github.com/svg/svgo)
+> TODO: Checkout <https://github.com/svg/svgo>.