Move Wasmtime for .NET to the Wasmtime repo.

This moves the Wasmtime for .NET implementation to the Wasmtime repo.

Wasmtime for .NET is a binding of the Wasmtime API for use in .NET.

crates/misc/dotnet/tests/Modules/TableExports.wat

@@ -0,0 +1,8 @@
+(module
+  (table $t0 1 10 funcref)
+  (table $t1 10 anyref)
+  (table $t2 100 1000 funcref)
+  (export "table1" (table $t0))
+  (export "table2" (table $t1))
+  (export "table3" (table $t2))
+)