Seq for nushell (#2704)

* seq command - WIP

* why, oh why

* works with parameters

* widths should've been optional

* dbg messages

* working. rest had to be first.

* updated so that it outputs a table instead of just strings

* made to work with floats, allowed separator be more than 1 char

* clippy

* fixed tests

* changed terminator help desc

* commit to get ci moving again

crates/nu-protocol/src/lib.rs

@@ -9,7 +9,7 @@ mod signature;
 mod syntax_shape;
 mod type_name;
 mod type_shape;
-mod value;
+pub mod value;
 
 pub use crate::call_info::{CallInfo, EvaluatedArgs};
 pub use crate::maybe_owned::MaybeOwned;