Add FullHelp.com

Hello! Thank you for the list! Its been quite useful several times. 🎉 

- [x] Your additions are ordered alphabetically.
- [x] Your additions are [Free software](https://en.wikipedia.org/wiki/Free_software), or if not they have been added to [non-free](non-free.md) and marked `⊘ Proprietary`.
- [x] If your additions depend on proprietary services outside the user's control, they must be marked `⚠`.
- [x] Your additions are not already listed at [awesome-sysadmin](https://github.com/n1trux/awesome-sysadmin) (IT infrastructure management), [staticgen.com](https://www.staticgen.com/) or [staticsitegenerators.net](https://staticsitegenerators.net/) (static site generators).
- [x] Your additions have their `License` main server-side `Language`/platform/requirement listed.
- [x] Any licenses you have added are in our [list of licenses](https://github.com/Kickball/awesome-selfhosted/blob/master/README.md#list-of-licenses).
- [x] You have searched the repository for any relevant [issues](https://github.com/Kickball/awesome-selfhosted/issues) or [PRs](https://github.com/Kickball/awesome-selfhosted/pulls), including closed ones.
- [x] If the main link of your addition points to the program's source code, there is no need to add a duplicate _Source Code_ link. The _Demo_ and _Clients_ links are not mandatory.
- [x] Any category you are creating has the minimum requirement of 3 items. If not, your addition may be inserted into `Misc/Other`.
- [x] Any software project you are adding to the list is actively maintained.

non-free.md

@@ -103,6 +103,7 @@
 ## Ticketing
 - [Jitbit Helpdesk](https://www.jitbit.com/helpdesk/) `⊘ Proprietary` - Self-hosted help desk software - simple but powerful. ([Demo](https://www.jitbit.com/hosted-helpdesk/trial/)) `ASP.NET`
 - [SupportPal](https://www.supportpal.com/) `⊘ Proprietary` - Powerful help desk software - easy, fast and intuitive. ([Demo](http://demo.supportpal.com/)) `PHP`
+- [Full Help](https://www.fullhelp.com/en/) `⊘ Proprietary` - Simple, easy to use help desk & knowledge base software. Custom branding, custom themes, restful API, communication channels, multi-company support, multi-language support, and much more! At least 1 new release per month. [Changelog](https://www.fullhelp.com/en/changelog) `PHP`
 
 
 ## Time Tracking