Baselining PHP client with Python/Ruby client and bumping version to 1.1.1.0

Signed-off-by: Yoav Schatzberg <yoav@siftscience.com>
Addressing Sarfaraz's PR comments.  Improved documentation and added brackets around single line if statement in Client constructor.
Merge pull request #14 from SiftScience/yoav_php_lib_global_api_key

(For Sarfaraz) Baselining PHP client with Python/Ruby client and bumping version to 1.1...