nfsv3: merge NameUtils and HimeraNfsUtils into single class

Motivation:
There are no reasons to have to utility classes in a single package
(plus Himera vs Chimera)

Modification:
merge NameUtils and HimeraNfsUtils into single class Utils class,
including corresponding tests.

Result:
same code, less classes

Acked-by: Marina Sahakyan
Target: master
1 job for master in 1 minute and 32 seconds (queued for 18 seconds)
Status Name Job ID Coverage
  Build
passed build #13571

00:01:32