Update clipboard feature (#2491)

* WIP - compiling but not working

* semi-working

* making progress

* working except for table lines

* fmt + clippy

* cleaned up some comments

* working line colors

* fmt, clippy, updated sample config.toml

* merges

* shouldn't these both bet clipboard-cli?

crates/nu-cli/src/commands.rs

@@ -18,7 +18,7 @@ pub(crate) mod cal;
 pub(crate) mod cd;
 pub(crate) mod char_;
 pub(crate) mod classified;
-#[cfg(feature = "clipboard")]
+#[cfg(feature = "clipboard-cli")]
 pub(crate) mod clip;
 pub(crate) mod command;
 pub(crate) mod compact;