Fix line wrapping in preview panes
Stop tracking todo.mkd files
Remove non-existant file from boilerplate load.js
Reorganize how extensions use the Preferences API
Add a preferences example to the extension boilerplate
Trigger and end links on mouseup event, not click
Update displayed link on individual preview
Improve pane open/close and clean up editor stylesheet

 - Panes can now be opened in between other panes
 - The open and close transitions are much smoother and more consistent
 - The editor stylesheets have been re-organized, and some small issues
   fixed (such as redundant selectors or lazy z-index values)
 - The editor stylesheets are now well-commented
 - The close command now waits for the pane to transition out before
   continuing
Don't throttle splitter drag handler
Rename info bar to title bar
Fix comment
Allow adding a pane without a transition
Document return value for Editor.addPane()
Tweak documentation
Fully implement the new link management UI, and some other changes.

  - Implement custom event system ala observable.js, but written in
    javascript, not coffeescript
  - Add mouse.js to allow easy access to the mouse
  - Use more semantic event names
  - Add more events to the Pane class
  - Replace the StatusLight class with the LinkManager class
  - Add the 'manage' command, which fades out pane contents and allows the
    user to rearrange pane links
  - Make sure that pane transitions finish before resolving command
    promises ('link', 'split_v', 'split_h' commands, plus the new 'manage'
    command)
  - Remove the box shadow from link lines to reduce lag
  - Improve how editor commands are dispatched and resolved (allow
    stacking multiple calls to Editor.runCommand()), and make the command
    history more useful
  - Allow breaking a pane's link without losing the current buffer
Refresh CodeMirror instances on pane resize
Tweak dialog styles and add 'title' option
Fix small CSS typos
Nail down a better style for dialogs
Add a background to each pane