Improve autocomplete performance

[Nattujessy]

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Current behavior

When i have 20+ rows with autocomplete component, the click event is take more than 4 seconds to get focused.
when i comment autocomplete component in data table it was working fine.
Earlier i had a same kind of problem with dropdown but primeng2.0 was improved the performance with dropdown. Similer kind of stuff are needed for autocomplete component as well.

Expected behavior

No performance issue with autocomplete component inside datatable rows.

Minimal reproduction of the problem with instructions

Steps to reproduce

1. Create the datatable with 13 columns (2 of them are autocomplete, 5 of them are dropdown, remains are input filed.
2. Add 20+ rows to it.
3. Click any drodown or text box component. You will see the delay time to get focused.
4. If u remove the autocomplete components you will see the fastness.
   Please tell us about your environment:

• Angular version: 2.4.8

• PrimeNG version: 2.0.1

• Browser: [all]

• Language: [all | TypeScript X.X | ES6/7 | ES5]

• Node (for AoT issues): node --version = 6.9.5

[Miosss]

+1, performance with a few (20+) rows and autocomplete is worse that using paper and pen