1. Added XML Header, this is conform according to https://www.w3.org/TR/SVG/struct.html
2. Added support for removing Byte Order Mark (BOM), this needed in some cases, eg. if the SVG is used as SSI (Server Side Include) in IIS (Internet Information Server).

SvgTextBase Text property setter resets Node collection to have single content node with provided text.

These shapes now render their fill, even if StrokeWidth less or equals zero.

RenderStroke method won't render the stroke if StrokeWidth is less or equal zero.

Added a test with a SvgText element where the whole text element was not written to XML of a deep copy of the SvgDocument.

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

SvgPointCollection.ToString method modified to return valid coordinate string with each coordinate pair separated by whitespace and their x and y values separated by comma.

reference: https://developer.mozilla.org/en-US/docs/Web/SVG/Element/pattern

This is huge especially for the low values because human eyes distinguish darker colors much better.

- Changed SvgImage.Href property from Uri type to String to avoid UriFormatException if Uri contains too much data
- Changed GetImage to receive a string instead of Uri object.
  - Created a temp Uri object in method with substring of allowed length and using this to determine Uri characteristics

Documentation reference.

- change separator
- add documentation reference to separator changing
- remove and sort usings

As long as the functions AdjustForViewBoxWidth and
AdjustForViewBoxHeight are not fully developed pay attention that the
ViewBox width and height will not mismatch the positions of the marker
element then one of them are zero.

This changes are based on Issue #212 from mater.

Add: Quick solution to avoid  ViewBox width or height zero calculation.
Add: UnitTests

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.

Load an attribute only once if possible.

Update to fix Draw(Height,Width) overload
#211 by OperatorOverload
Pull Request from master

Split by comma, remove space in the end
#209 by ifcwebapp
Pull Request from master

Add: SvgShapeRendering, SvgTextRendering and SvgImageRendering in
SvgAttributeCollection.IsInheritValue

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.

The rectangle path width/height was computed using the full stroke width.
It should have been using the half stroke width instead.

Fix #185: Multiline text is not rendered. Tspan is nested/child element to text element and it was not considered for path

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.