* [C#] Fix and improve project files
* "net35" target included for Unity 5
* "net46" target included for Unity 2017
* "netstandard2.0" target included for Unity 2018 and general use
* "netstandard2.1" target included for Span<T> support
Included project properties for defining UNSAFE_BYTEBUFFER, BYTEBUFFER_NO_BOUNDS_CHECK, and ENABLE_SPAN_T conditional compilation symbols.
* Add documentation on building for C#
* [C#] Fix and improve project files
* "net35" target included for Unity 5
* "net46" target included for Unity 2017
* "netstandard2.0" target included for Unity 2018 and general use
* "netstandard2.1" target included for Span<T> support
Included project properties for defining UNSAFE_BYTEBUFFER, BYTEBUFFER_NO_BOUNDS_CHECK, and ENABLE_SPAN_T conditional compiler constants.
* Add documentation on building for C#
* [C#] support Object API
* fix sign-compare
* fix indent
* add new line before for loop.
* using auto whenever possible
* reduce the amout of blank lines.
* wip: support vectors of union
* done: support unions of vectors
* set C# version to 4.0
* remove null propagation operator
* remove auto property initializer
* remove expression-bodied method
* remove pattern matching
* add Example2 to NetTest.sh
* separate JavaUsage.md and CsharpUsage.md from JavaCsharpUsage.md
* add C# Object based API notes.
* support vs2010.
* remove range based for loop.
* remove System.Linq
* fix indent
* CreateSharedString to CreateString
* check shared attribute
* snake case