Enhance sorting and filtering APIs

[Shlomi Assaf]

• - Make the API's more clear
• - Support filter predicates through column definitions (like sorting)
• - Align sort and filter APIs to match as much as possible
• - Expose filtered and sorted data through PblDataSource
• - Document filtering

[Egor Korovin]

would be great to have access to filtered data. at least to count, i.e. to be able to show how many items stayed after filtering

also selection column should select only items which visible after filtering.

[Shlomi Assaf]

@ek2dev @tsiegleauq See the docs in the Features -> Column -> Column Filters page

version 1.0.0-alpha.23