remove method
Removes an entry from persistent storage.
Implementation
Future<bool> remove(String key) async{
final String prefixedKey = '$_prefix$key';
_preferenceCache.remove(key);
final bool isRemoved =await _store.remove(prefixedKey);
if(isRemoved){
_streamController.add(<String,dynamic>{
'key':key,
'value':null,
'changed':true
});
}
return isRemoved;
}