Rename version from 6.0.0-SNAPSHOT to 6.0.1-SNAPSHOT in preparation for the 6.0.1 release
unification of persistence and transaction handling for jbpm and human task

(cherry picked from commit a0547526c1602899f1daf566b3f1c65a9a9727dc)
added missing environment key
Fixed version in docbook
 - updating image in docs for correct update site url
documentation: Various minor corrections and updates.
(cherry picked from commit de106aae60c43c6083c35666862b5f1fc67fe066)
documentation: Additional minor corrections and updates (as suggested by laune).
(cherry picked from commit 76bf1eab142945445263df08e07a5dfa675b4b45)
[DROOLS-381] allow to explicitly remove a KieModule from the KieRepository
(cherry picked from commit 342a3b24e0bb66af48f6811d7f4066f00f907d36)
Improved and fixed the security docs

(cherry picked from commit fcb5a1fb355dfa3ae146db0578a69cc1ff5e6656)