Support iOS 8.4.1 and safety IE9/10

don't try to nest parent in child Sortable

fix "Cannot read property 'destroy' of undefined"

fix multiline float + move below

Correct spelling error in README.md

* update from RubaXa

when nesting Sortable's, we're not interested in this error:
"HierarchyRequestError: Failed to execute 'appendChild' on 'Node': The new child element contains the parent."

check for existence of dataTransfer

As done in the other place where `dataTransfer` is used.
This is to support fake html5 drag and drop events, where `dataTransfer` is not accessible. Use case: Selenium testing with ePages-de/chromedriver-html5-dragdrop

Added some Setup steps

Knockout sortable #488

Fixed how we find correct indexes for items if the sortable is
bound to a filtered collection.

Fixes #488

#356 Fixing issue of dropping on the right end of horizontally laid out drop zones

#356 Fixing issue where dropping an item on the right end of a horizontally layed out drop zone does not add the item

Update dependency of mongo-collection-instances

fix flex containers in row mode 

meteor: option to specify collection selector