Add regex bean matching, and regex key search/replace to normalize names

This patch adds two more config items to the JolokiaCollector.conf
mbeansre:  works like mbeans: but matches with regularexpressions
rewrite: which allows rewrite pairs in order to rename collected keys before data is passed to the handler
You're probably right here, so replacing = with _  is not a big change (just remove it from the dot replacement), and the non-alpha replacement will change it into a _.   As for leaving the old code in there, I did so for reference as this kind of discussion is much easier.  
How do you feel about the bracket removal, vs switching them to _ (older behaviour).  As a new user of this plugin, I found the output pretty damn ugly, but I do understand your concerns about breaking existing.