According to https://developer.mozilla.org/en-US/docs/Web/SVG/Attribute/transform
translate transformation can be specified without second parameter

* fill can be null -> none in XML
* added type converters for enums
* added type converter for unitcollection
* fixes several viewbox bugs
* document can now draw into a given bitmap
* content of SVG tag is written (used by the text tag)
* changed font handling in text element, still need proper alignment
* changed intersparse character of SvgTransformConverter.cs to space, because inkscape couldn't parse comma
* added class diagram for basic shapes

- Adding initial support for Write functionality. Units & Transforms mostly. Enums still need work. Needs support for an IsDirty concept so that that every possible attribute isn't written.

- Fixed "#7522 support rotate(angle,cx,cy)". Added new properties and a new constructor overload to   SvgRotate in order to support the optional parameters.
- Removed redundant code from SvgElementFactory.

- Made all transforms (SvgTranslate, SvgMatrix etc) sealed types.

- Added initial custom/querystring 'parameters' implementation (#5652)