Merge pull request #346 from shaitan/lts

Monitor&Doxygen: Added doxygen code documentation to monitor. (lts)
logger: logger construction from the interface must *NOT* set default log-level, users should not be tricked here and potentially find out later, that their logging is being done only on INFO and ERROR levels
Merge branch 'lts' of github.com:reverbrain/elliptics into lts
Merge branch 'lts' of github.com:reverbrain/elliptics into lts