Fix Core SDK v2.5.x compatibility
Merge pull request #66 from RamyTalal/patch-1

Fix Core SDK v2.5.x compatibility
Updated Samples to use latest merchant-sdk-php and sdk-core
Update readme with correct version.

It should match what is in the samples to avoid any kind of confusion.
Merge pull request #82 from usmanhalalit/patch-1

Update readme with correct version.
- Fixing Logging Mechanism
- Updating User Agent
Merge branch 'namespace-php5.3' into stable-php5.3