- conforms to CSS specs - use default value if value is empty
- fixes #318

* use element applies referenced viewBox scaling
* created FontManager

- prevents crash, fixes #223

- fixes W3C example painting-marker-04-f.svg

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

- fixed stroke and fill color (taken from marker or from included path)
- added missing scaling for markerUnits="strokeWidth"
- fixed initial value of "orient" to be "0"
- fixes 2 of the W3C tests

- handle markers on paths with successive equal points
 (fixing drawing of __issue-345-01.svg)

- fixes #342

- added failing test for #318

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

- fixes #191

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

- fixes #58

- added "stroke-dashoffset" support
- added "painting-stroke-04-t" to "PassingTests" (csv/txt)
- fixes #388 

- added a few of them to passing image comparson tests

- added image broken by regression to tests (__Flag_of_the_United_States)
- added some passing issue specific tests to image comparison tests

- first try for a matching comparison test
- compares down-scaled gray-scale images pixel-wise
- see #378