fixes issue with not properly loading conf file
fixes issue with not properly loading conf file

This commit addresses an issue that would prevent the client from loading
the conf file from the users home folder.  The load_config method did not
properly expand the ~ for obtaining the full path to the conf file.

This commit is required to support loading conf files from the users
home folder

mitchmahan/pyeapi,jerearista/pyeapi,arista-eosplus/pyeapi,devtodor/pyeapi-py3,SivagnanamCiena/pyeapi,mzbenami/pyeapi