use a anonymous namespace and sane function names

Change-Id: I8fdd5fb4f21e6c90e352089858ce98a62ac213de
handle autocomplete with dot in formula name, fdo#80058

The problem is that a dot is a word separator so the break iterator
provided by ICU will think that the dot separates two words whereas it
is part of the name here.

Change-Id: I73cee4304f83888b1645fec7b1851b9f42ef879f