Release notes: SpyFu v4.15

** Bugs Fixed
* [SF-19034] – Account – Allow users to see the entirety of their API usage
* [SF-19191] – Wrong label in the navigation menu for PPC Overview

** Story
* [SF-19190] – Marketing: SpyFu Affiliate Page is live

** Improvement
* [SF-19173] – Adding Keyword Group and Label indicators on the Keyword Universe Tab
* [SF-19181] – Fix PDF styling issue on URL overview
* [SF-19187] – Leads – API requests are being truncated by URI length limits
* [SF-19188] – Ad History – Increase maintainability of ad versioning
* [SF-19263] – URl API – Improve empty query handling for public organic keywords endpoint