- Added BOOST logging in the style of dcdbpusher
- All logging-related functionality is in logging.h

- Sensor cache is now based on circular arrays (actually vectors)
- CacheEntry class supplies a list of helper methods to ease access
to the cache (might be useful for dcdbpusher also)
- Thread safety for cache access is still to be verified (either way,
mutexes are not viable)

- The collectagent is now configurable, like dcdbpusher
- Available config options can be seen in the sample collectagent.conf file
- Supplying a path containing config files is mandatory, like dcdbpusher;
this may change in the future
- Please do a make all && make install from the root of the repo to update
scripts and directories that were modified to add config support

Rework DCDBQuery::doQuery() and DCDBQuery::genOutput() to leverage proper regular expressions for function-, sensor-, and modifier-parsing.

- MQTT publish messages that have a topic preceded by the /DCDB_MAP/
keyword will be interpreted as sensor name auto-publish messages
- The payload of such messages is a string defining a sensor name, that
is used together with the MQTT topic to perform a "sensor publish"
action on the Cassandra db, like dcdbconfig does

Bugfix: Parse for functions and modifiers in a sensorname string first, then lookup the actual sensor name in the DB

- Collectagent will not hang anymore when pushers crash or terminate abruptly without properly closing their connections
- Issue was related to message buffers not being cleaned up in SimpleMQTTServerMessageThread upon a connection release

See https://github.com/cpp-netlib/cpp-netlib/pull/637

Introduced a bit mask for sensor properties in dcdblib and dcdbconfig (e.g., integrable, monotonic,...)

Added functions like Deltas, Integrals and Derivatives to queries. Still need to fix unit conversions and scaling factors for all functions.