Merge branch 'stable-php5.3' into namespace-php5.3
Fixing incorrect variable name
Change the minimum requirement of the SDK
Merge pull request #59 from RamyTalal/patch-1

Change the minimum requirement of the Core SDK
Updated README referencing composer

Removed references related to install script
Updated README referencing deprecation

Modified the second point on installer script too.
Merge pull request #61 from prannamalai/namespace-php5.3

Merging in pull request for deprecation notice for custom installation
Merge pull request #62 from paypal/namespace-php5.3

Namespace php5.3