riak 3.x `riak chkconfig` command returns non-zero on success

[tburghart]

Per the relx extension script contract, extension scripts should exit with an appropriate result code.

riak/rel/files/riak-chkconfig does not do this (the two other extension scripts do), and therefore picks up the non-zero exit provided by the relx-generated bin/riak script.

The solution is to add the following (or something like it) to the end of the rel/files/riak-chkconfig file:

--- a/rel/files/riak-chkconfig
+++ b/rel/files/riak-chkconfig
@@ ...

 echo $CUTTLE_CONF
+
+# No explicit exit from within script or tools, assumed to have succeeded.
+exit 0