Revamp configuration

Move to an Hadoop/HBase style configuration where local configuration
properties are specified in `honeycomb-site.xml`, and local environment
variables are specified in `honeycomb-env.sh`.  The JVM classpath is
specified by the `HONEYCOMB_CLASSPATH` env variable, and the JVM options
are specified by the `HONEYCOMB_JVM_OPTS` env variable.  Java side
configuration properties are picked up from `honeycomb-default.xml`, and
then `honeycomb-site.xml`.  The environment variables must be set on the
process starting MySQL, so sourcing `honeycomb-env.sh` inside
`mysql.server` is probably the easiest way to do that.