Unsafe versions of standard library `From<T>` and `Into<T>`.
# Install
```toml
[dependencies]
unsafe_from = "1.0.0"
```
# Use
```rust
use unsafe_from::UnsafeFrom;
struct MyUnsafeType(i32);
unsafe impl UnsafeFrom<i32> for MyUnsafeType {
unsafe fn unsafe_from(t: i32) -> MyUnsafeType {
MyUnsafeType(t)
}
}
```