Added Math filter collection:
1. when mirroring a field - added its configuration - so mirroring an ItemLink will most probably add you a dropdown filter
2. when not mirroring a field - added 3 different types of filters - fulltext/initial/exact matches. You can use each of them like this:
{filter field="..." editable="y"} to use fulltext
{filter field="..." editable="initial"} to use initial match - e.g. matching 123 in 123USD
{filter field="..." editable="exact"} to use exact match - useful for searching identifiers or things that are not matched via fulltext - stopwords like Y/N yes/no, etc.
Added range filter to Numeric field. To use it:
{filter field="..." editable="range"}