Allow for actual configuration files to be specified on command line, not just configuration directories. Add exception handling to main of pusher, collectagent, grafanaserver

Don't fetch the OPA libraries when they are already installed via RPM. Add the OPA plugin to the list of plugins to be built by default.

- New filtering methods applies a filtering regular expression to all
node names in the node list of a job; the mode of the filtered node names
is then computed, and the job is processed only if this matches an
arbitrary "match" string
- Can be used to assign jobs to different islands in a HPC system based
on the allocation of nodes

- Allows to reduce the size of the query results considerably

- Uses an overloaded version of the querySensor() method

- overloaded query() and fuzzyQuery() methods that allow to query a set
of sensor IDs at the same time
- also changed the behavior of fuzzuQuery(): only one query is performed
now, retrieving the most recent value BEFORE the specified timestamp

- Allows to print the covariance matrices of the gaussian mixture model

- Can be used to increase the number of data points for model training

- Suppressing an integer comparison warning

- Implemented "means" REST API action
- Integrated the Mahalanobis distance outlier cut

- A plugin based on gaussian mixture models to enable clustering for
performance variation analysis or outlier detection