This library parses the input text containing a number in scientific format like
```
1234.5678e-2
```
and converts it to a number, represented by the following tuple
```
(sign, mantissa-hi-64-bits, mantissa-lo-64-bits, exponent)
```
Example:
```Rust
use scidec::{Number, number_from_string};
let result = number_from_string("1234.5678e-2");
match result {
Number::Fin(false, 0, 12345678, -6) => {}
_ => panic!()
}
```