title: Conflict with sublime hotkey
body: <p>I am working with the sublime 3 text editor. I am modifying the User version of the keymap, however, it does not seem to be replacing the default keymap hotkeys. Specifically, in the Default keymap, I see the following assigned for the "copy" hotkey:</p>
  
  <pre><code>{ "keys": ["ctrl+insert"], "command": "copy" },
  { "keys": ["ctrl+c"], "command": "copy" },
  </code></pre>
  
  <p>There are two hotkeys assigned for the copy command, and I am not sure why. I use the latter command in my User keymap, but the hotkey is not working. The ctrl+insert hotkey is the one that is taking precedence. </p>
  
  <p>Is there a way to modify the Default keymap for Sublime? </p>