Add no_std and forbid(unsafe) in utils

utils/float/src/lib.rs

@@ -1,5 +1,5 @@
 //! The Float type used throughout the ecosystem
-
+#![no_std]
 #![cfg_attr(feature = "fast-float", feature(core_intrinsics))]
 
 /// Type used for floats, configure with the `f32` feature
@@ -12,9 +12,9 @@ pub type Float = f64;
 /// Associated constants for [`Float`]
 pub mod consts {
     #[cfg(feature = "f32")]
-    pub use std::f32::consts::*;
+    pub use core::f32::consts::*;
     #[cfg(not(feature = "f32"))]
-    pub use std::f64::consts::*;
+    pub use core::f64::consts::*;
 }
 
 #[cfg(feature = "fast-float")]