Remove if(trace) checks wherever possible

Citing from David Lloyd's email:

<snip>
If you're using the jboss-logging API, and your log statement does not
do any interpolation, then it is just as fast to do any of the following
(with no if):

log.trace("blah");
log.tracef("the %s happened to %s", foo, bar);
log.tracev("the

happened to

", foo, bar);

In the case where trace logging is disabled, these are exactly as
efficient as the if (log.isTraceEnabled()) variants. In the case where
it is enabled, it is marginally more efficient (though the trace log
itself is substantially more expensive of course).

Overall I'd avoid the "if" forms unless you're doing complex interpolation:

log.trace("Foo " + bar + " baz " + zap);
log.tracef("the %s happened to %s", fooMethod().barMethod(), bar);

...both of which incur the expense of the expression resolution even if
the log message is ultimately discarded.

</snip>

This JIRA is about:
1. removing all the "if (trace)" statements from the code (where possible, see below)
2. making sure that this is a documented policy and people are aware of it