P12 Key: allow providing the private key directly

Different versions of openssl support different P12 key formats the
key from google wasn't supported by the version of open we were using
so it was easier to allow supplying the private key directly.
Updated Bigquery.php
Merge pull request #87 from silvolu/master

Style fixes
Updated Groupssettings.php
Updated Doubleclicksearch.php
Added service QpxExpress.php
Updated Compute.php
Updated IdentityToolkit.php
Merge pull request #28 from iFixit/private-key--allow-direct-usage

P12 Key: allow providing the private key directly
Adding test for private key checking

Adding test, and avoid spinning up preg engine.
Merge and modification of #36

Adding Curl support, including tests.
Fix typo in exception

Resolves #84
Merge pull request #93 from ianbarber/master

Curl support and direction private key modifications
Fixed comment in Curl.php
Updated Bigquery.php
Fix use of PHP 5.4+ short array syntax
Fix short array in cURL and add cafile support

Use default CA file if non provided.
Merge pull request #97 from ianbarber/master

Fix short array syntax usage
Style fix
Updated YouTube.php