Lots of async changes

spec/multi_line_spec.rb

@@ -0,0 +1,13 @@
+describe 'a multi-line suggestion' do
+  it 'should be displayed on multiple lines' do
+    with_history(-> {
+      session.send_string('echo "')
+      session.send_keys('enter')
+      session.send_string('"')
+      session.send_keys('enter')
+    }) do
+      session.send_keys('e')
+      wait_for { session.content }.to eq("echo \"\n\"")
+    end
+  end
+end