An option to Use Custom SVGs

[Divij Sehgal]

Technically, this defeats the goal of having this library that works with Iconify Icon-sets. This recommendation, however, comes based on a project I used this in.
For one of the figures we could not find the ideal icon in any of the available icon-sets on Iconify. So the design team came up with a custom SVG that we used.
In order to keep the code-base uniform by using this library across the code-base, it would be a really useful feature to have a custom SVG option into it for the odd scenario where one cannot find their icon on the iconify catalogue.