This reverts commit 37c55aa5.

As far as I can see there's no way to determine if a request is in transit. I'm open to suggestions if e.g. @betullam knows more.

I suspect the same changes should be done to the other two methods, but I don't currently have a way of testing it.

- Highlighting of selected hierarchy items was broken by commit 2e6a78ad.

- Wrong associativity of ternary in filters.phtml
- Missing default restoration in edit history action

- Resolves VUFIND-1353.

- Allows the cover router to operate in more contexts (CLI vs. web)

- Only affected PostgreSQL databases.
- We needed to better standardize the way the search object data was normalized.

- Avoids checking for existing records when we know there shouldn't be any duplicates.
- Moves setting source identifier of records inside the collection class to make it faster.

- In addition to making code more flexible, implement full support for the Search2 backend.

- Use properties to allow subclass overrides.

- Useful for supporting additional search backends.

- Makes subclassing possible without cache collisions.

- Prerequisite for supporting multiple backends in hierarchies.

Also makes sure that status is not fetched multiple times for an item if same container was used twice.

- Translations courtesy of Dr. Pragya Pandey, Mr. Komal Patel, Dr. Md. Nurul Alam and Prof. Parhasarathi Mukhopadhyay.