JBIDE-13781 : add maven-acr-plugin to projects having an app-client dependency

Signed-off-by: Fred Bricon <fbricon@gmail.com>
JBIDE-13781 : extend m-acr-p support to all type of projects

Signed-off-by: Fred Bricon <fbricon@gmail.com>
JBIDE-13847 - AS 7.2/EAP 6.1 aren't recognized correctly
JBIDE-13849 - ConcurrentModificationException exception in Source Lookup plugin
JBIDE-13847 : refactor source lookup tests

Signed-off-by: Fred Bricon <fbricon@gmail.com>
JBIDE-13804, JBDS-2490 JBoss Tools Central Discovery plugin has moved to https://github.com/jbosstools/jbosstools-discovery; remove old READMEs and deprecation notes; add new note to root README.md