Bhv 11576 Prevent unnecessary refresh() in DataRepeater.js

Issue
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When we remove some models from DataList, it makes another refresh() in DataRepeater

Cause
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Currently DataRepeater always execute refresh() whenever remove event sender is collection

Fix
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Decouple selection logic which DataList needed from `modelsRemoved` in DataRepeater.js

Enyo-DCO-1.1-Signed-off-by: David Um david.um@lge.com
@clinuz 
*I changed notifySelectedModels  to deselectRemovedModels)

{{modelsRemoved()}} in DataRepeater has two roles.
1. deselectRemovedModels
2. refresh()

What DataList needed is the first role, we do not want refresh again. That's the reason why I removed it.

deselectRemovedModels() is still necessary in DataList.
Because DataList also has selection feature.
You can simply testify what is difference between calling it or not via DataGridListSample.
If we do not call this method,  {{_selected}} in DataRepeater still contain model instance after it removed.