Fix memory leak in features_config.c

Fix memory leak in features_config.c

The options should not be registered multiple times. Instead, the configuration just needs
to be reprocessed by the config framework. This also exposed that we were not properly telling
the config framework to treat the configuration processing with the "reload" semantics when
a reload occurred. Both of these errors are fixed now.

Thanks to Richard Mudgett for discovering the leak.

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@391676 65c4cc65-6c06-0410-ace0-fbb531ad65f3