Preparing fro release 3.10

adding nugetdoc.md

minor updates to nuget package

Updating readmes and nuspec before NuGet release. Final commit of ver…

…sion 2.8

Seek Improvements and Indexing (unosquare#280)

* starting with seek indexing. Related to issue unosquare#139

* continued work on seek indexing.

* Generalizing sorted binary search algorithm. Continued work on seek indices. See issues unosquare#250 and unosquare#139

* improved and simplified seek logic.

* minor renaming and added seek error checking.

* logging when using a video seek index entry.

* fixing frame start offset by offseting them by main component.

bumping up version before release

Preparing for 4.0.250 release

Preparing for 2.40 release

Release 230 Final commit.

Release 3.4.220 is now final.