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
We need to be careful with how drastically the namespacing logic changes. Completely rewriting the keys will cause graphite to write completely new metrics. Essentially this will cause historical queries to become harder (the series will be split into two) and will double up the disk space required in graphite. 

We need to make sure that any changes are providing significant value, and are reasonable defaults. Ideally, any problems ("..") would get fixed, but the general behavior will stay the same. 

For example, here's a before and after the changes:

```
# before
servers.vagrant-ubuntu-precise.jmx.org.apache.cassandra.transport.type_Native-Transport-Requests.TotalBlockedTasks

#after
servers.vagrant-ubuntu-precise.jmx.org.apache.cassandra.transport.type.Native-Transport-Requests.TotalBlockedTasks
```

Specifically, `type_Native-Transport-Requests` became `type.Native-Transport-Requests`.

I don't think replacing "=" with "." is the right behavior. That implies a hierarchy can be derived from the bean names. This may or may not be true. Per the JMX specification, the key/value pair ordering can be arbitrary. For this reason, the collector actually sorts them alphabetically (via flag passed to Jolokia). As a side effect this more or less removes any hierarchical nature. Here's an example:

![example](https://cloud.githubusercontent.com/assets/2858322/5398320/4ade5a68-812f-11e4-9fb5-e768c796e0d5.png)

In addition, the hierarchy is already fairly deep from the java package name. The best behavior would probably be to have completely flat bean names. e.g.) `type_Foo_name_Bar`, although, again, we need to be careful about changing the namespace. A good compromise might be to do only the bare minimum here (escaping "bad" characters) and allow users to add specific more rules.