Partially revert last commit: Remove Logging file; instead every class/object gets his own logger as member-variable

Also fix 2 compiler warninge (signed-unsigned compare)

Reintroduce -v command line option
Reworked (partially reverted to previous state) how cmd-line options and global config-options are read in

2 Bugfixes:
-correct initialization of PDUSensors with new()
-cooldown value for XML-file refresh is now correctly converted from MS to NS

Remaining TODOs:
network logic to obtain XML-file
use appropriate lock when sensor accesses PDUUnit
make reading XML more generic?
Test it!

Every sensor stores its full MQTT-topic now

Add possiblity to specifiy plugins in the global.conf
Rename plugins to libdcdbplugin_pluginName.so
Add version number to plugin-names

Remove readme.txt from perfevent

Add possibility to compile with symbol DEBUG (use "make debug")
Minor fixes and improvements to debug-output

Add missing -rdynamic flag to the linking of dcdbpusher
Fix double-free error when destructing a Template-Sensor

Finished rework of sysfs-files.
Adapted and improved various other involved classes.
TODOs remaining:
-adapting Makefile for automated compilation of librarys
-solving runtime errors when trying to run dcdbpusher with sysfs

Removed no longer required files from SYSFSSensor
Renamed SYSFS to Sysfs
Introduce Configurator-base class, derive SysfsConfigurator from base-class

Add generic Sensor-base class
Rework dcdbpusher + MQTTPusher to use generic base class

Add perfpusher-files.
Together with sysfspusher this should be enough for a start. Add other pushers later when dcdbpusher is working.