This reverts commit a7097113.

This reverts commit 480a54d8.

Based on Issue #204.
Now users can add customer fonts/ private fonts to
SvgElement.PrivateFonts.

Unit Test:
Add Test: PrivateFontsTest
Add Resources from PrivateFontsTest.
Add SvgTestHelper
Change MultiThreadingTest, now based on SvgTestHelper to use shared code
(no code duplication)

Note:
MuliThreadingTest TestFile is not available. The vvvv/master should add
the test file to the resources or other developer can not test the svg
engine.

Fix:
Now the application make sure to set back the old culture even an error
occurred.
SvgColourConverter.ConvertFrom
SvgPathBuilder.ConvertTo
SvgDocument.Write
SvgExtentions.GetXML

Add:
Attribute: "shape-rendering"

Change:
- Many other properties were unknowingly overloaded. I changed them to
override.
- Some methods or structures need the [CLSCompliant(false)] Attribute.
For example the Enums.TryParse extension. This extension has the where
condition IConvertible. IConvertible is [CLSCompliant(false)] and that
the reason why it is correct to mark the Enums.TryParse extension also
as [CLSCompliant(false)].
- Property "float Opacity" in SvgElement was unknowingly overloaded in
SvgGradientStop as string [stop-opacity]. In the end this property was
only used as float. I changed the SvgGradientStop.Opacity property from
string to float and to override.

W3CTTestRunner: Added a console log at the bottom to avoid annoying message boxes popups and to have a log to copy with a contextual menu to easily report errors.

W3CTestRunner: Added the code to infer the right directory separator for the current OS. Now doesn't crash anymore on Mac OSX.

Fixed problems when running in multiple threads. The use of a static matrix and the use of StringFormat.GenericTypographic seemed to cause problems when used in multi-threading. This is resolved by making the matrix non static and use a copy of the StringFormat.

Also created a new exception for memory overflows. When using multithreading to render a large amount of big images the bitmap creation can fail (due to memory allocation) throwing an error. This is now caught and a specific exception is thrown.

More serialization bug fixes and better fallback for font definition
problems.

Added parameter to the SvgAttribute indicating whether the storage is
the _attribute dictionary.  If true, the output will only be serialized
only if the key is in the dictionary.  This structure is an alternate to
the SvgDefinitionDefaults class.

- Improving rendering of SVG images
- Allow markers on lines, polygons, and polylines
- Implement different line joins and line caps
- Improve CSS handling

- Better parser for dealing with parsing edge cases
- Fix corner radius for rectangles
- Fix to gradients.  Most tests now pass
- Add the possibility for a fallback paint server
- Initial fixes to clipping
- Start marking passed test
- Fixes to pattern rendering

- Fixing path parsing algorithm to deal with nuanced arc cases and
hopefully improve performance
- Attempts at better memory management
- Working toward getting symbols to render correctly

- 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

- Support of generic fonts (serif, sans-serif, monospace)
- Initial support of filters
- Fixes to gradient rendering

- Remove WPF dependency
- Fix compilation error after merge
- Add support for underline and strike through
- Fix whitespace handling with text rendering

- 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.
- ...