Update feature-pack.adoc (#4435) (#4518)

Link to mavencentral with pom snippets

Co-authored-by: Ben <ben.wilson@vaadin.com>
Co-authored-by: Petter Holmström <petter@vaadin.com>

Author: 3 people

articles/tools/modernization-toolkit/feature-pack.adoc

@@ -17,6 +17,10 @@ Feature Pack is a part of the Modernization Toolkit. It's a collection of classe
 
 Feature Pack replaces the older Classic Components project which sought to be close drop-in replacements for several Vaadin 7 and 8 components and classes. As a part of the Modernization Toolkit, Feature Pack goes beyond Classic Components in its setup in a few ways. 
 
+For more information on the APIs and components inside this library, see the https://vaadin.com/api/com.vaadin/vaadin-feature-pack-flow/[API docs]. 
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+To start using Feature Pack in your Maven or Gradle project, see the documentation at https://central.sonatype.com/artifact/com.vaadin/vaadin-feature-pack-flow
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 pass:[<!-- vale Vaadin.Versions = YES -->]
 
 == Differences from Classic Components