Remove Ticksel (#1902)

This service has entered the Sunset phase. On December 31, 2020, the Ticksel service reached the end of its useful life (“EOL”).

Ref 1: https://www.ticksel.com/
Ref 2: issue #1902 

resolve #1902

README.md

@@ -172,7 +172,6 @@ API | Description | Auth | HTTPS | CORS |
 | [ORB Intelligence](https://api.orb-intelligence.com/docs/) | Company lookup | `apiKey` | Yes | Unknown |
 | [Smartsheet](https://smartsheet-platform.github.io/api-docs/) | Allows you to programmatically access and Smartsheet data and account information | `OAuth` | Yes | No |
 | [SwiftKanban](https://www.digite.com/swiftkanban/) | Kanban software, Visualize Work, Increase Organizations Lead Time, Throughput & Productivity | `apiKey` | Yes | Unknown |
-| [Ticksel](https://ticksel.com) | Friendly website analytics made for humans | No | Yes | Unknown |
 | [Trello](https://developers.trello.com/) | Boards, lists and cards to help you organize and prioritize your projects | `OAuth` | Yes | Unknown |
 
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