Enabling setting of loglevel in EtchRuntime for default logger

An additional constructor for the EtchRuntime makes it possible now to set
the log level for the default console appender.

Change-Id: I19ab47ca7d6fb941a38e7e952a40ab954efd84f9

git-svn-id: https://svn.apache.org/repos/asf/etch/trunk@1578908 13f79535-47bb-0310-9956-ffa450edef68