TableViewSectionedDataSource default parameters don't reflect iOS default behavior

[Sascha Gordner]

I've stumbled across #359, where the table swipe actions introduced with iOS 11 don't work, unless you implement dataSource.canEditRowAtIndexPath = { datasource, index -> Bool in return true }.

This issue arises from the default values set in TableViewSectionedDataSource:

RxDataSources/Sources/RxDataSources/TableViewSectionedDataSource.swift

Lines 40 to 41 in e4ffaaf

 canEditRowAtIndexPath: @escaping CanEditRowAtIndexPath = { _, _ in false }, 
 canMoveRowAtIndexPath: @escaping CanMoveRowAtIndexPath = { _, _ in false }, 

Apple Docs state:
tableView(_:canEditRowAt:)

... If this method is not implemented, all rows are assumed to be editable. ...

tableView(_:canMoveRowAt:)

...By default, the reordering control is shown if the data source implements the tableView(_:moveRowAt:to:) method.

The current default values require a developer using tableView(_:leadingSwipeActionsConfigurationForRowAt:)/ tableView(_:trailingSwipeActionsConfigurationForRowAt:) to explicitly return true for canEditRowAtIndexPath - which is not necessary when doing it without RxDataSources.
Therefor, both closures should return true to mimic iOS' default behavior.