Add posibility to edit head of resolv.conf

Queries take long time as the dns entry that resolve the query is
added at the end of the resolv.conf. This fix helps to add dns entry
to head of the file rather than the base.

Related-PROD: PROD-36892
Change-Id: I506e6d3b27c14d810d37a7ec13f98f143ef7694e
3 files changed