Remember collapse state of entries within file when re-opening file

[distefam]

I frequently use the toggle collapse feature for entry contents (see #80) to gain a cleaner view of my project when trying to "zoom out" and see the entire project at a glance. When closing and re-opening a file, however, one must again re-collapse all entries' contents, making it frustrating to navigate away from the file once I've gotten all entries' contents collapsed.

There are two possible ways to address this that I can see:

1. remember the toggle state of an entries contents (and/or properties, timestamps, etc.)
2. add a shortcut to toggle the selected property for the entire file (zC, for example--in contrast with zc--could toggle the contents for all entries in a file).

[NorfairKing]

@distefam you might be using files that are too big.

The starting position logic is designed to bring you directly to the right entry with the right collapsing. Maybe you can take advantage of it more effectively?

In any case there's no way to remember collapsing I think.