Use newer TPs
JBIDE-15281: Move to Tycho 0.18.1

Support for Maven 3.1.0
[JBIDE-13795] Incorrect URL for JBoss Jira on readmes
[JBIDE-15256] Include source gen plugin for feature into pluginManagement

Add plugins involved in feature source generation into pluginManagement
JBIDE-11319: Eclipse-SourceReferences