Optimize EditPickerHelper::LoadValues and MInputHelper::LoadValues methods

Optimize EditPickerHelper::LoadValues and MInputHelper::LoadValues methods, so in case if they use kDBList class object (e.g. called from kDBTagProcessor::PrepareListElementParams method), then they will query requested data for all list records at once and not by one query per list element as for now. Also they could cache query result, because they won't be changed during this script run.

These LoadValues methods are used to display data from fields, that use "inp_edit_picker" and "inp_edit_minput" blocks on editing form.