Added no_std attribute to prevent compile errors

[Frago9876543210]

This should fix the compilation error of no_std crates that depends on that macro. This error probably comes because panic handler included twice during compilation.

#[panic_handler]
fn panic(_: &core::panic::PanicInfo) -> ! {
    loop {}
}

error[E0152]: found duplicate lang item `panic_impl`
  --> src\main.rs:35:1
   |
35 | fn panic(_: &core::panic::PanicInfo) -> ! {
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: the lang item is first defined in crate `std` (which `const_utf16` depends on)
   = note: first definition in `std` loaded from \\?\C:\Users\alex\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\x86_64-pc-windows-msvc\lib\std-09e4abccd169ee6e.dll, \\?\C:\Users\alex\.rustup\toolchains\nightly-x86_64-pc-windows-msvc\lib\rustlib\x86_64-pc-windows-msvc\lib\libstd-09e4abccd169ee6e.rlib

[rylev]

Looks great! Thanks 😄

[Frago9876543210]

@rylev could you make a release?

[rylev]

@Frago9876543210 New release has been pushed.