Added comments to openEntrySvc angularjs methods.
Changed openEntrySvc methods to that they potentially could work with several entries open at once.
Fix: when opening an entry, if the user has not selected the "open all entries" checkbox, any other open entry is closed.
When loading entries from the server, if the user has selected the "open all entries" config option, new entries are shown open by default.

The default behavior is the same as until now: new entries are shown closed by default, and at most a single entry is open at a given time (if the user opens an entry, any other open entry is closed).