Version 1.16.0 Stable

• Add the market plugin's link on installation page
• Plugin removal from the settings page
• Ability to add a custom user agent from the settings page
• [Trying multiple user agents for parsing feeds](https://github.com/LeedRSS/Leed/commit/
  e0d8aaa)
• Full feed url displayed on synchronize
• Technical chores

Full Changelog: v1.15.3...v1.16.0