Crucial updates to Google Geocode API integration and DPD webservice WSDL URL's

[wardcapp]

Commits within the pull request contain following required updates to get the module running (using Magento 1.x):

• Updated the Google Geocoding integration to meet recent requirements by Google. Earlier integration is broken / does not center the Google map upon checkout.
• Updated Google API key generation instructions, mentioned when configuring the shipping method, as well.
• Corrected the DPD webservice WSDL URL's / endpoints to the actually working paths (those currently mentioned within the master branch return 404 pages).

[Detzler]

Thanks for your branch @wardcapp. I was going insane about the branch confusion and the invalid API endpoints. Somebody needs to merge this branch into master immediately.