* use element applies referenced viewBox scaling
* created FontManager

- prevents crash, fixes #223

- transformations in the marker drawing element have been ignored
- fixes #215

- removed debug break in marker end test that made it very slow
- added link to release notes in Wiki

- fixes #342

- added failing test for #318

- set correct default for fill/stroke unset color
- fixes #398

- added test image for new issue
- all passing W3C images shall now correctly be shown in passing tab

Fix issue with percentage unit in "stroke-width", now taken from the viewbox width/height normalised diagonale for x/y elements e.g. circle
Test images and svg under #338

Fix Issue #385, using TextBounds.Width rather than path bounds to ensure proper font alignment for "middle" and "end" - see also "text-align-03-b"

- added a few of them to passing image comparson tests

- ignore textLength attribute if X attribute is list
- add test images

- Fix: adjustment is wrong in lengthAdjust='spacingAndGlyphs'.
- Add test images.

- ensures that #243 is fixed

- calculate svg element bounds considering child svg fragments
- consider svg fragment offset in bounds / dimensions
- do not create view box if none is defined
- fixes #244

- a view box does not need a clip region, this breaks the overflow
handling
- overflow handling:  handle overflow attribut "Inherit" as Visible and
"Scroll" as Hidden as per W3C documentation
- fixes #279

If the root svg uses transformations ( e.g. defines a viewBox and
different width and height) the nested svg areas are misplaced or
invisible.

- Extraction interface for SvgRenderer
- Initial support for Text on a Path
- Initial support for Svg Fonts
- Support for symbol element
- Minor bug fixes with image pattern rendering
- Additional support for Text whitespace modes

- Adding W3C test cases and a test fixture
- Fixed support for CSS stylesheets (particularly when class names are
referenced)
- Refactoring unit calculations so that percentages and fractions
calculate more accurately
- SvgImage:
- Support PreserveAspectRatio attribute
- Support for referencing svg images
- Refactored text rendering to use the AttributeCollection inheritance
scheme
- Initial attempt at 'ex' unit support
- Added support for system color names
- Changed parsing of entities to support XML entities
- Supporting loading of a svg document directly from a XmlDocument with
requiring serializing the document as a string first.
- ...