Update Pdo.php

fixed #106
Merge branch 'develop' of http://github.com/bshaffer/oauth2-server-php into develop
better readme - SQL code samples and DSN explanation
more README fixes - better method organization
places Grant Types above Response Object - it is more interesting
standardizes code block format and intendation
remove json highlighting
Change Statuscode 400 to 405 if POST-Request is required

As per http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html#sec10.4.6 change the statuscode from 400 to 405 and include `Allow`-header indicating that POST must be used to grant an access token.
Merge pull request #110 from steffkes/develop

Change Statuscode 400 to 405 if POST-Request is required
Better support for unbounded scopes.
Check client's allowed grant types for authorize requests #111

Add checks for restricted grant type to Authorize Controller.
Means that clients need 'implicit' grant type to use implicit flow, and
clients that can't use auth code flow get bumped on the authorization step
not the token step.
Move checkRestrictedGrantType() to ClientInterface

Make more sense to have checkRestrictedGrantType in ClientInterface instead
of ClientCredentialsInterface as its not really anything to do with
'credentials'.

Revert AuthorizeController $clientStorage parameter to ClientInterface
Fixing OAuth2_ServerTest::testAddingResponseType

Make mock storage return TRUE for 'checkRestrictedGrantType'
Fix undefined index 'client_id' errors in OAuth2_Server_Authorize_* Tests
Update README.md

fixes #114 - changes "locahost" to "localhost"
Merge pull request #109 from bojanz/unbounded_scopes

Better support for unbounded scopes.
Merge pull request #112 from rjmackay/develop

**BC-BREAKING CHANGE** - moves `checkRestrictedGrantType` from `ClientCredentialsInterface` to `ClientCredentialsInterface`. See #111 and #112
Update Server.php

**BC-BREAKING CHANGE** - addresses #108 - removes default jwt granting, as "audience" is required.  This needs to be set using `addGrantType` instead.
Merge branch 'develop-before-grant-type-refactor'
increments tag in readme