Finish making the textview plugin optional

Cargo.lock

@@ -1927,6 +1927,7 @@ dependencies = [
  "nu-parser",
  "nu-protocol",
  "nu-source",
+ "nu_plugin_textview",
  "num-bigint",
  "num-traits 0.2.10",
  "onig_sys",
@@ -2084,7 +2085,6 @@ version = "0.1.0"
 dependencies = [
  "ansi_term 0.12.1",
  "crossterm",
- "nu",
  "nu-build",
  "nu-errors",
  "nu-protocol",

Cargo.toml

@@ -22,6 +22,7 @@ nu-source = { version = "0.1.0", path = "./crates/nu-source" }
 nu-protocol = { version = "0.1.0", path = "./crates/nu-protocol" }
 nu-errors = { version = "0.1.0", path = "./crates/nu-errors" }
 nu-parser = { version = "0.1.0", path = "./crates/nu-parser" }
+nu_plugin_textview = {version = "0.1.0", path = "./crates/nu_plugin_textview", optional=true}
 
 query_interface = "0.3.5"
 typetag = "0.1.4"
@@ -114,6 +115,7 @@ binaryview = ["image", "crossterm"]
 sys = ["heim", "battery"]
 ps = ["heim"]
 starship-prompt = ["starship"]
+textview = ["nu_plugin_textview"]
 #trace = ["nu-parser/trace"]
 
 [dependencies.rusqlite]

crates/nu_plugin_textview/Cargo.toml

@@ -10,7 +10,6 @@ edition = "2018"
 syntect = { version = "3.2.0" }
 ansi_term = "0.12.1"
 crossterm = { version = "0.10.2" }
-nu = { path = "../.." }
 nu-protocol = { path = "../nu-protocol" }
 nu-source = { path = "../nu-source" }
 nu-errors = { path = "../nu-errors" }

crates/nu_plugin_textview/src/main.rs

@@ -1,8 +1,9 @@
 use crossterm::{cursor, terminal, RawScreen};
 use crossterm::{InputEvent, KeyEvent};
-use nu::Plugin;
 use nu_errors::ShellError;
-use nu_protocol::{outln, serve_plugin, CallInfo, Primitive, Signature, UntaggedValue, Value};
+use nu_protocol::{
+    outln, serve_plugin, CallInfo, Plugin, Primitive, Signature, UntaggedValue, Value,
+};
 use nu_source::AnchorLocation;
 
 use syntect::easy::HighlightLines;