Added Tidelift information (#144)

Author: GrahamCampbell

.github/FUNDING.yml

@@ -0,0 +1 @@
+tidelift: "packagist/gitonomy/gitlib"

README.md

@@ -10,3 +10,15 @@ It makes shell calls, which makes it less performant than any solution.
 Anyway, it's convenient and don't need to build anything to use it. That's how we love it.
 
 *Documentation*: http://gitonomy.com/doc/gitlib/master/
+
+---
+
+<div align="center">
+	<b>
+		<a href="https://tidelift.com/subscription/pkg/packagist-gitonomy-gitlib?utm_source=packagist-gitonomy-gitlib&utm_medium=referral&utm_campaign=readme">Get professional support for Git lib with a Tidelift subscription</a>
+	</b>
+	<br>
+	<sub>
+		Tidelift helps make open source sustainable for maintainers while giving companies<br>assurances about security, maintenance, and licensing for their dependencies.
+	</sub>
+</div>