mruby-eval

This is a package I made for another lib, but here's how to use it:

```rust use mruby-eval::{evalto, evaluators::evalto_string};

evaltostring("1+2") // returns an Option, in this case Some(String::from("3"))

evalto!(i32, "1+2") // evalto! returns an Err // (# in ParseError is the type, ex: ParseIntError) // // So in this case it's Ok(3)

```