Settings v2.0.0

This release switches the namespace from Sparks\Settings to CodeIgniter\Settings, and introduces $contexts that allow you to store more customized settings.

What's Changed

• Update Toolkit by @MGatner in #12
• Apply coding standard by @MGatner in #13
• Helper Nulls by @MGatner in #14
• Config Injection by @MGatner in #15
• Contexts by @MGatner in #16
• Service Configuration by @MGatner in #17
• Namespace by @MGatner in #18

Full Changelog: v1.0.0...v2.0.0