WIP: Virtual scroll with item size as any expression
fix: default data to empty array
feat: add grid
test(list-fit): update styles
demo(collection-repeat): add basic demo
demo(collection-repeat): make item height look better
demo(collection-repeat): add filter
fix(ionHeaderBar): do not tapScrollToTop for inputs

Fixes #1199
collection-repeat: enable grid functionality
collectionRepeat: fixes
demo(collection-repeat): contacts
collectionRepeat: rerender on resize
demo(collection-repeat): use min files
demo(collection-repeat): fix error
demo(collection-repeat): only show letters that match searched names
demo(collection-repeat): update name to 3000 contacts
demo(collection-repeat): comments, make simpler
demo(collection-repeat): add clear button
demo(collection-repeat): scrollTop when filtering
demo(collection-repeat): hide letters while search is focused