3.0.1 BUG:    config 'outputobj' mgnt

3.0.2 BUG:    replacing specific PEAR LOG constants
               by PHP constants (PEAR_LOG_DEBUG -> LOG_DEBUG etc)

3.0.4 UPDATE: making iCalcnv constructor log argument optional

3.0.5 NEW:    new config 'extension_check',
              default TRUE, if to check input file extension

3.0.6 UPDATE: removed internal function 'iCaldate2timestamp',
              moved 'fixiCalString' to a static private function

3.0.7 BUG:    cvs2iCal and mgnt of escaped characters in input