Add support for filtering index property values

[Nicklas Nordborg]

Some items have properties that are indexed collections. The use case here is the minValue and maxValue properties of Annotation types (see #1986). They are mapped as a Map<String, String> via Hibernate which has support for queries like:

options['minValue'] = '0' and options['maxValue'] = '100'

In principle, an indexed property is like a regular property with a slightly different syntax. In ticket #1986 we have already added support for exporting mapped properties using the syntax: @map-name(key). It should be possible to use the same syntax also for filtering. Note that we can't use [] since that interferes with the support for multi-row filtering (see #1912).

[Nicklas Nordborg]

(In [7105]) Fixes #1991: Add support for filtering index property values

Implemented on the annotation types 'Min value' and 'Max value' columns.