FacebookRequestException now extends FacebookSDKException so all SDK exeptions can be caught by referencing FacebookSDKException only.
Checking for malformed signed request
Merge pull request #33 from bartekn/checking-malformed-signed-request

Checking for malformed signed request
Merge pull request #7 from SammyK/better-exception-extension

FacebookRequestException now extends FacebookSDKException
Use PSR-4 loading instead of classmap