- Always save it.
 - Having no FIUs in a config file is no longer an error
 -

Also,
 - no longer support FIU_CFG_BITS from .ini file,
 - rename injection to inject (about everywhere).

The 'optional' attribute of function parameters is documented but not implemented?!

 - objectify connection and configuration handling
 - work around Doxygen::Filter::Perl issue
 - add some missing documentation bits
 - make some functions private
 - always send 0 bytes to reset connection at the beginning

Also, add a proprietary license till an open-source one has been chosen.