added a proposes fetchEach method

the fetchEach method fetches a sequential array of all rows from the database and apply a callable function to each found row
added testFetchEach test

test the fetchEach Method added to AbstractConnection.php
Added the callback parameters to fetch/* methods
Added tests for the added callback parameter in fetch/All/Assoc/Col/Pairs Methods
Merge pull request #48 from nyamsprod/develop

add a callable to apply to fetch*() results