Improve task information display

[chiphogg]

This includes what to display, as well as how do display it.

The current policy omits the section names, displays the project hierarchy in blue, and shows the task name highlighted according to priority. This is the right balance for some (e.g., an "ISBA Conference" project with a "Register" task -- I can see I need to register for the ISBA conference; I don't need to repeat myself). However, for other tasks, it shows too much information (especially for very deep projects) and for other tasks, too little (e.g., blog post project names often don't hint they're blog-related).

Also, it's extremely helpful to show the comments in the list, but some comments are very verbose and take up way too much room.

Ideas?

• Two-line display, with the task name on the second line (unless it's a standalone task).
  • Augment j/k to go to next/prev action (instead of line) -- this may be a good idea anyway.
• Toggle display of extra context with keyboard shortcuts
• Instead of showing comments, indicate which posts have comments by a symbol (perhaps *@ instead of @).
  • If we implement "Tree View" as in #3, hitting <Enter> would show the comments. This seems very natural.
• Indicate in the file itself which sections/projects should be included/omitted.
  • I don't really like this idea, but it might work.