Import OLM Contacts to Gmail

How to import OLM contacts to Gmail? Was one of the biggest obstacles for all those usual users who were unable to Import Outlook Mac address book in Gmail since they did not had any effective tool one like OLM Contacts Migrator which can easily convert OLM contacts to Gmail without altering the Data-Information of OLM file. Besides this it also lets one to migrate Contacts from Mac Outlook to Gmail along with the Email Headers, Properties etc.