feat(repl): run "deno repl" with no permissions (#16795)

This commit changes "deno repl" command to run with no permissions by
default and accept "--allow-*" flags. 

This change is dictated by the fact that currently there is no way to
run REPL with limited permissions. Technically it's a breaking 
change in the CLI command, but there's agreement in the team 
that it has merit and it's a good solution.

Running just "deno" command still starts the REPL with full permissions
allowed, but now a banner is printed to inform users about that:

1 files changed, 12 insertions, 4 deletions

diff --git a/cli/tools/repl/mod.rs b/cli/tools/repl/mod.rs
index afbd39eff..502105139 100644
--- a/cli/tools/repl/mod.rs
+++ b/cli/tools/repl/mod.rs
@@ -1,5 +1,7 @@
 // Copyright 2018-2022 the Deno authors. All rights reserved. MIT license.
 
+use crate::args::ReplFlags;
+use crate::colors;
 use crate::proc_state::ProcState;
 use deno_core::error::AnyError;
 use deno_runtime::permissions::Permissions;
@@ -77,8 +79,7 @@ async fn read_eval_file(
 pub async fn run(
   ps: &ProcState,
   worker: MainWorker,
-  maybe_eval_files: Option<Vec<String>>,
-  maybe_eval: Option<String>,
+  repl_flags: ReplFlags,
 ) -> Result<i32, AnyError> {
   let mut repl_session = ReplSession::initialize(worker).await?;
   let mut rustyline_channel = rustyline_channel();
@@ -92,7 +93,7 @@ pub async fn run(
   let history_file_path = ps.dir.repl_history_file_path();
   let editor = ReplEditor::new(helper, history_file_path)?;
 
-  if let Some(eval_files) = maybe_eval_files {
+  if let Some(eval_files) = repl_flags.eval_files {
     for eval_file in eval_files {
       match read_eval_file(ps, &eval_file).await {
         Ok(eval_source) => {
@@ -114,7 +115,7 @@ pub async fn run(
     }
   }
 
-  if let Some(eval) = maybe_eval {
+  if let Some(eval) = repl_flags.eval {
     let output = repl_session.evaluate_line_and_get_output(&eval).await?;
     // only output errors
     if let EvaluationOutput::Error(error_text) = output {
@@ -127,6 +128,13 @@ pub async fn run(
   if !ps.options.is_quiet() {
     println!("Deno {}", crate::version::deno());
     println!("exit using ctrl+d, ctrl+c, or close()");
+    if repl_flags.is_default_command {
+      println!(
+        "{}",
+        colors::yellow("REPL is running with all permissions allowed.")
+      );
+      println!("To specify permissions, run `deno repl` with allow flags.")
+    }
   }
 
   loop {