Add "eof" action which closes the finder only when input is empty

Close #289

test/test_go.rb

@@ -718,6 +718,19 @@ class TestGoFZF < TestBase
     end
   end
 
+  def test_eof
+    tmux.send_keys "seq 100 | #{fzf "--bind 2:eof"}", :Enter
+    tmux.until { |lines| lines[-2].include?('100/100') }
+    tmux.send_keys '123'
+    tmux.until do |lines|
+      lines[-1] == '> 13' && lines[-2].include?('1/100')
+    end
+    tmux.send_keys :BSpace, :BSpace
+    tmux.until { |lines| lines[-1] == '>' }
+    tmux.send_keys 2
+    tmux.prepare
+  end
+
 private
   def writelines path, lines
     File.unlink path while File.exists? path