This patch add the load of deployer-input automatically, if exists in
default path (~/tempest-deployer-input.conf).
It also add the option to not load it, with --no-default-deployer
This will fix the cases that user miss to add --deployer-input and
tempestconf miss some configuration due of that.
Change-Id: I17ce46bac06158dd3cca298f33c6ea929051fb06