Allow 10-digit tricodes and custom on/off-suffixes

Some systems such as "Elro AB440S" make use of ten digit tricodes and use different suffixes for on/off.
These fields are added to the `rc-switch` preferences (i.e., separate for every single switch), which allows parallel usage of different systems.

Tested with "Elro AB440S". Previous setups should still work. This fixes issue #46.