This is first of all consistent with all of the other (similar) factories, and secondly it will also simplify a future addition of a corresponding `NodeSVGFactory` (if that's ever deemed necessary).
- Some js files contain scale factors for each glyph in order to rescale Liberation to have a final font with the correct width.
- A lot of XFA have some containers where their dimensions are based on their text content, so using default font from browser can lead to an almost unreadable pdf.
Given that these factories are being used in *different* files, for Browser respectively Node.js implementations, it seems reasonable to move them into their own file instead.
