fixed namespace of PPConfigurationException

the PPConfigurationException class is not in the used \PayPal\Auth namespace
Merge pull request #7 from futjikato/master

fixed namespace of PPConfigurationException set to \
Update README.md
updated stubs
adding auth capture samples
adding delete credit card sample
testcases updated

updated testcases to match new json schema
and updates with camel case function names
updating stubs to have fluent setters and retaining deprecated methods
Update lib/PayPal/Rest/RestHandler.php

Updating namespace of PPConfiguration exception thrown by the handler
adding new testcases for Auth Capture
Updated stubs to support namespace
upgrading to namespace based SDK core
updating sample to show full API flow
updated code comments to reflect on groc docs
updating index with new samples
passing API context to create authorization
removing duplicate use
regenerated stubs
changing the HTTP method
new stub