Factorized char normalization code out to normalize7bit.[hc] .

Factorized char normalization code out to normalize7bit.[hc] .

Removed unnecessary tests and assert
on service conf_metadata, as  those are now
satisfied on service creation time (in config.c in function
conf_metadata_assign()) once under startup, and not every time a new
record is to be parsed.

Removed unneeded logging when  service->merge == Metadata_merge_no .

Replaced manual record allocation with call to record constructor.

Replaced loop to find conf_metadata field_id with call to
conf_service_metadata_field_id().

Replaced manual record_metadata allocation with call to
record_metadata_create(se->nmem).

All these changes have been made with safety guards following this idom:
#if 0
  //oldcode
#else
  /newcode
#endif
such that they can be reverted easy if need might be. The #if guards will of
course disapear, when we have confirmed that the code behaves exaactly the
same as before.