Extract helpers from load_options_hash_from_file

This method was doing too match. Make it a little more cognitively
manageable by splitting it out into multiple helper methods.

Change-Id: I5226b4c94986eb438f2fa3ffc4048d73321cc650
Reviewed-on: https://gerrit.causes.com/31890
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Shane da Silva <shane@causes.com>