Re-ordering tools and fixing comments and log messages.
Adding extremely cool features to the RRD model

1) Ability to split a multi-ds RRD into a list of single-ds RRDs
2) Ability to merge a list of single-ds RRD into one multi-ds RRD

In both cases, the data sources and the general structure must be the
same.

With this operations, it is possible to re-implement
opennms-rrd-converter that supports RRDtool and JRobin seamlessly,
and order of magnitudes faster.