Removed a FIXME from KNXCoreTypeMapperTest regarding Calimero's handling
of daylight savings time (DST) in DPT 19.001.
Added testing against multiple timezones included zones with and without
DST.
Comments revised
Merge pull request #1310 from Snickermicker/knx_dst_fixme

[KNX] FIXME removed from Testcase