Fix #185: Multiline text is not rendered. 

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

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.

Fix to #173: Sub elements in group element are not rendered

Extended the Marker start/mid/end getters to return null if none

Extended the Marker start/mid/end getters with a function to return null if the property was set to none. This will prevent nullpointer issues when having none as one of the items.

Added new Draw method

Skip to consider Symbol element directly, because it is calculated through reference from use element

Fix #55 : Call Path in a SVG with an empty content element causes an InvalidArgumentException[updated]

Infinite loop in SvgRadialGradientServer CalcScale

Fixed viewbox transaltion when altering the aspect ratio

FIxed #132  - rendering inline images

HSL support, fix for clip path (issues 142 and 143)

Merge branch 'simplify-element-writing' of https://github.com/JoshMcCullough/SVG into JoshMcCullough-simplify-element-writing

Conflicts:
	Source/SvgElement.cs

Fixed attributes/enums.

Infinite loop in SvgRadialGradientServer CalcScale Issue #163

Fixed some spelling mistakes

Fixed #145 - SVG incorrectly renders <title> elements.

SvgDocument as Write(XmlTextWriter); allowed elements to decide whether or
not they should be written. E.g. text elements should not be written
unless they have children.

Fixed many attribute enums. Now they will 1) output the proper case, 2) only output if non-null and non-default, 3) include more documentation, 4) are marked as Flags where appropriate.

Revert "Working on making this export valid SVG documents."

Working on making this export valid SVG documents.