Multi thread

[marcoregueira]

This requests makes GenFu thread safe, allowing shared access to registration engine.
Of course that doesn't means deterministic: if active threads register different rules for each type it could cause interferences because of the shared static storage.

There are two commits in this request.

First one: Add tests. They are all red.
Second: Go for green.

[ScarletKuro]

Why this is not merged? Looks like the author doesn't develop this library actively anymore.
This problems (#143) (#143) are pain in the ass

[marcoregueira]

@ScarletKuro You can use https://www.nuget.org/packages/GenFu.Instantiable.NonOfficial/1.3.4-preview.

Aside of thread safety it adds support for creating Genfu instances.

Source code is here, https://www.nuget.org/packages/GenFu.Instantiable.NonOfficial/1.3.4-preview, if you prefer to build the code yourself.

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Edit.
Mobile devices are evil and my fingers too big. Source code is here. :)
https://github.com/marcoregueira/genfu