OpenXML Filter: XLSX: expose numbers, dates and booleans as metadata

This is a follow-up to issue #1062 (closed).

We are extracting inline (issue #982 (closed)) and shared strings as metadata. And it would be reasonable to have numbers, dates and booleans extracted as well.

Below is a sample document for references:

And here are some peculiarities of it:

  1. Number

2. Boolean

3. Date

4. Date-time

5. Number function

6. String function

For more details please refer to the attached document.