Remove first 2 arguments that added before invocation to every module.
Fixed #164. Changed drupalgap_node_assemble_data() to not place empty values in the data string. Thanks to @amitsedai for the code.
Merge pull request #163 from khayong/7.x-1.x-alpha

Remove first 2 arguments that added after invocation to every module.
#139. Added hook_image_path_alter(). Changed drupalgap_image_path() to call hook_image_path_alter(). Removed hard coded Amazon S3 feature, and moved to contrib module.
#139. Changed drupalgap_image_path() to generate the default path, if no hook_image_path_alter() implementors modified the path.
Resolving conflicts