C# projection layer

[maxgolov]

Implement pure cross-plat .netcore -compliant C# PInvoke projection layer on top of C API.

[maxgolov]

Several customers would benefit from that implementation:

• AzIP plugin for Office
• other Office plugins in general
• MRW in Unity Editor (.NET 4.6)
• other customers who'd need a full-fledged cross-platform .netcore implementation with UTC channel

[maxgolov]

• no timeline for OTEL (Office has their own wrapper in their own repo, not merged back yet
• discuss timeline for MRW with @reyang

[maxgolov]

MRW shipped with existing SDK. Currently there's no commitment to work on PInvoke-based C# netcore projection. This issue is not resourced, but up for grabs by anyone willing to support this scenario.

[maxgolov]

There's some reference example how to implement a wrapper in this PR #231 ... This work is not complete, but at least giving an idea how one may implement a C# wrapper on top of C API.