DNSimple get_domain also accepts domain name

As the real DNSimple behaviour, get_domain also accept a string argument.
[google] Expose Google API client, compute and api_url for easier debugging
Rackspace/examples; cloudfiles directory is set to public, therefore file is accessible.
Update rubygems to fix travis in ruby 1.8
Fix typos that make ruby 1.8 break
Merge pull request #2572 from andjonno/master

Rackspace/examples; cloudfiles directory is set to public, therefore fil...
Merge pull request #2568 from josacar/master

[dnsimple] make get_domain also match to domain name
Merge pull request #2573 from maestrodev/google-debug

[google] Expose Google API client, compute and api_url for easier debugging
Merge pull request #2574 from maestrodev/travis-fix

Update rubygems to fix travis in ruby 1.8
merge with fog master branch