* Changes for the next version of the EventPipe file format

* Added Versioning support, documentation

* Update V3 format for Event MetaData

This simplifies the V3 format.  I also spit out the code for the old format
so it would be easier to remove it later.

* nits

* making it work with the latest format

* padding support

* get ProviderId based on ProviderName, assume Metadata is mandatory and it's lenght does not come first

* update the tests

* update test file after merge of my fork with CoreCLR/master

* update C# version for all projects

* improvements after code review

* improvements after code review

* aligning change: after the block size comes eventual padding