Support for Intertechno Self Learning models in RFM12 ASK

Newer models of the Intertechno remote controlled switches use a
different protocol as default. Now absolute dimmer values can be sent.
Works with arctech based designs from several other vendors.
corrected indents for rfm12 ask
Some changes to RFM12 ASK Intertechno self learning

corrected ecmd_feature
changed command to rfm12 intertechno_sl
added to Configure.help
changed bitorder when sending housecode and device
if dim value is present dim is sent instead of ON.
ECMD was too long
Merge pull request #255 from neffs/master

Support for Intertechno Self Learning models in RFM12 ASK