Updates the readme.

README.md

@@ -1,2 +1,12 @@
 # jitsi-utils
-A set of basic Java/Kotlin utilities used in jitsi projects.
+This project contains a set of basic Java utilities used in Jitsi
+projects.
+
+The aim is to reduce the interdependency between the different Jitsi
+projects. For example we used to place code which needed to be shared
+between ice4j, libjitsi and jitsi-media-transform in ice4j. This was
+not great, because neither libjitsi not jitsi-media-transform need
+to depend on ice4j.
+
+This project's external dependencies should be kept to a minimum, and 
+it should NOT depend on any other Jitsi project.